Web Sustainability Guidelines (WSG) Quick Reference

This document provides a quick reference to the Web Sustainability Guidelines (WSG) specification. An at-a-glance overview is also available.

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Introduction

This quick reference showcases success criteria for each guideline. Checkboxes are provided for individuals or groups wishing to work through the list though your progress will not be saved. This document is print friendly if you require such functionality.

User Experience Design

Identify, assess, disclose, review, and mitigate sustainability impacts Review the planet, people, and prosperity impacts of your project at the start and at regular intervals. Record the main issues you identify, where improvements are needed, and the progress you make. Reflect these findings in your public-facing governance documents and project reporting. Create a plan to reduce the non-digital environmental and social impacts of digital activities associated with your project. Include impacts from logistics and delivery emissions, infrastructure emissions, local health effects, and supply chain pressures. Use measurable actions to improve external planet, people, and prosperity outcomes.

Understand user requirements or constraints Identify the primary and secondary users, and affected communities, for the project. Use research, testing, analytics, and reviews to understand their needs and the project's impact on them. Involve users throughout the project.

Integrate sustainability into every stage of the ideation process Optimize approved branding materials and assets to meet the organization's sustainability requirements before release and review them regularly after launch. Where brand guidelines exist, include information about the environmental impact of materials and assets, along with guidance for sustainable production, use, and disposal. Use wireframes and rapid prototypes to test ideas early, build agreement quickly, reduce risk, and avoid unnecessary development work and resource use. Use participatory design methods throughout the design process. Involve users in testing and iteration, and give communities opportunities to share their knowledge and experience to improve the product or service. Address planetary needs and environmental boundaries during the ideation phase. This can include creating non-user, non-human personas, such as animal- or planet-focused perspectives, and developing climate-specific user stories and sprints.

Design efficient and streamlined user journeys Make tasks simple and efficient to complete. Help users understand what is required at the start of a task, reduce unnecessary choices, and show how long journeys are expected to take. Design user journeys that are clear and efficient. Use established design patterns that people already understand. Provide a human-readable sitemap, especially for large, complex, or legacy websites where navigation is not straightforward. Keep it regularly updated. Provide clear and accessible navigation and search features so users can quickly find the content or services they need. Use lightweight and efficient ways to help users discover new content and services, including news pages, updates, and changelogs.

Design to assist and not to distract Ensure users can control when and how they receive information, while respecting their attention, focus, and mental effort. Show users information relevant to their current task and avoid unnecessary interruption and competing interface elements. Delay or collapse information not immediately needed, but keep it easy to find. Only show pop-ups, modal windows, or other disruptive interface elements when the user chooses to open them. Use decorative design only when it improves the user experience, and make optional assets removable or turned off by default. Do not remove information or functionality that may be important for accessibility, safety, or different user needs. Avoid design patterns that engage users longer than necessary, such as infinite scroll or disabling standard browser controls and navigation features.

Avoid being manipulative or deceptive Avoid deceptive design patterns that pressure or mislead users. This includes practices such as bait and switch, hidden fees, or fake scarcity. Clearly label advertisements and sponsored content. Deliver advertising in a lightweight and minimally disruptive way while enabling users to control the experience. Remove unnecessary analytics and tracking, and respect user consent over tracking analytics. Optimize content for search and social sharing in ways that support user needs rather than manipulation. Do not misuse accessibility features, create low-quality content, or add unnecessary duplication only to influence search rankings.

Make deliverables understandable and reusable Create documentation and other deliverables in reusable formats to reduce duplicated work and support long-term sustainability. Document functionality and technical requirements in clear and easy-to-maintain resources. Keep documentation updated over time and provide guidance for replacing or retiring outdated information. Provide developers with access to source code and code comments so they can easily understand, maintain, and reuse the code.

Use a design system for interface consistency Use a design system for large projects or projects with many contributors to improve consistency, performance, and long-term sustainability. Use reusable components based on web standards, load only the components needed for each page or feature, and maintain the system through clear ownership, versioning, and updated documentation. Follow established design patterns and conventions.

Optimize media to reduce resource use Only include media when it supports user experience or improves understanding and keep the number of media items to a minimum. Resize, optimize, and compress media for different screen sizes, devices, and user needs. Use widely supported, efficient formats that enable native presentation or playback where possible. Avoid unnecessary custom or non-native media players. Use hardware-accelerated playback when available and compatible with security requirements. Incorporate lazy and/or deferred loading from the start by identifying which media elements are required immediately and which should load only on user interaction. Load large or data-intensive media only when needed, using a non-functional static facade or placeholder to defer loading until user request or interaction. Disable autoplay for audio, video, and other media by default. Ensure users can control playback and resolution. Inform users about media length, format, and expected data use. Provide the option to disable data-intensive media or offer lower-bandwidth alternatives. Create a media management and usage policy. Include guidance on compression, rendering performance, file formats, data retention, storage, review, and deletion.

Ensure animation is proportionate and easy to control Use animation only when it supports the user experience or helps users understand content or actions. Limit the number and frequency of animations to reduce distraction, lower resource use, and avoid affecting device performance. Set a maximum number of replays or iterations. Let users start, pause, stop, or control animated and moving content. Keep interactive and animated content as lightweight as possible. Reduce rendering cost by accounting for formats, lengths, complexity, dimensions, quality, tooling, and implementation approach. Where multiple approaches are available, choose browser- or platform-native animation capabilities and minimize main-thread or layout-intensive work.

Use optimized web typography Use system fonts or other pre-installed fonts to reduce font downloads and improve performance. Limit the number and complexity of downloaded fonts. When using variable fonts, restrict supported axes and ranges to only those required by the project to reduce file size. Use the most performant font formats available and provide suitable fallback fonts to maintain readability and performance during font loading or when custom fonts cannot be loaded. Remove unused font styles, weights, and character sets. Subset fonts based on explicitly supported languages, scripts, and Unicode ranges required by the project. Where you have full control over all input and output, subset fonts to include only the relevant Unicode ranges or character sets. In cases involving dynamic content or user-generated input, provide broader script coverage and use Incremental Font Transfer (IFT) to load required font segments on demand.

Avoid unwanted notifications Only send notifications that match user preferences or that the user has explicitly requested. Avoid unnecessary emails, (SMS) messages, and push notifications. Give users clear control over each notification type. Let users manage their notification and messaging settings easily. Make unsubscribe, logout, and account closure options visible and accessible. Turn off optional notifications by default and enable them only after user opt-in.

Reduce the impact of downloadable and physical documents Design workflows to reduce the need for paper documents. When paper use is necessary, reduce paper use through efficient print layouts and minimal page counts. Include print style sheets and test them with real content. Encourage the use of digital formats instead of paper storage and archiving. Optimize and compress downloadable documents, provide them in accessible formats that suit different user needs, and choose open, widely supported formats (such as HTML) over proprietary file formats. Avoid duplicating work. When a document is reused, generate and store it once on the server so it can be reused efficiently, preferably on a cookie-free domain. Show users the document name, format, size, and a short summary before download. Let users choose the most suitable format and language. Avoid embedding documents directly in pages; instead provide download or browser-view links.

Involve users early in the project Create defined processes for prototyping and testing new features and interface components. Validate them with representative users to ensure they work in real-world conditions and across different needs.

Audit and test for bugs or issues requiring resolution Evaluate current user experience and check the codebase for bugs, identify performance issues, and account for accessibility, sustainability, or security problems at appropriate regular intervals, such as every month or quarter. Maintain an automated test suite that covers critical functionality and run it consistently during builds and releases to catch regressions early. Identify and resolve bottlenecks or issues in the underlying code or infrastructure which could impact sustainability and performance to encourage a smooth, frictionless user journey. Consider both simulated and real-world metrics. Monitor performance across every release cycle using appropriate tooling or through research and auditing.

Validate usability through testing and real-world usage Monitor user feedback, adoption, and churn for each feature. Use these insights to guide updates and future releases. Use usability testing, real user metrics, and user interviews throughout product development. Measure the impact of findings and check whether released features meet user needs and internal goals.

Cross-platform compatibility support Document supported devices, operating systems, and browsers, including version ranges. Review and update it regularly to reflect current releases. Avoid planned obsolescence. Keep compatibility for as long as reasonably possible. Clearly explain whether updates are major changes that may affect performance or smaller updates that fix issues or improve security. Test for a wide range of user conditions, including slow, restricted or unstable connections, Virtual Private Network (VPN) use, different operating systems and browsers, and older or low-performance devices.

Web Development

Set goals based on performance and energy impact Set clear performance and environmental goals for the project, including limits on requests, elements rendered, or other measurable resource use. Prioritize lower-impact design choices, paying attention to measurable differences in energy use across components. Complex structure, styling, and script-driven experiences along with graphics-heavy and media-rich rendering increase the computational complexity of rendering. Use more intensive approaches only where these add clear value.

Minify and remove unused code Minify code and data files by removing unnecessary whitespace, comments, and non-essential characters. Apply this consistently across the system to reduce file size and improve loading efficiency. This helps reduce cumulative data transfer and processing overhead at scale, improving resource efficiency and lowering energy consumption. Identify and remove unused or dead code, especially in CSS and JavaScript.

Modularize bandwidth-heavy components Split large or bandwidth-heavy components into smaller modules that load only when needed. Avoid excessive splitting, as it can increase overhead, reduce caching efficiency, and make code harder to maintain.

Avoid redundancy and duplication in code Refactor code to reduce duplication and redundancy by improving structure, consolidating repeated logic, and encouraging reuse. Prioritize improving and extending existing user-facing solutions over rebuilding them from scratch. Only replace an existing solution when doing so provides clear benefits to user experience, performance, scalability, or maintainability. Apply DRY (Don't Repeat Yourself) principles to CSS and JavaScript where they improve maintainability. Ensure that efforts to reduce duplication do not increase complexity, introduce unnecessary dependencies, or adversely affect performance.

Treat third parties the same as first parties Review third-party content and/or services early in the design or ideation process, including plugins, widgets, feeds, maps, carousels, tracking scripts, and similar components. Use as few as possible, preferring lightweight options to reduce overall environmental impact, including GHG Protocol Scope 3 emissions. Ensure third-party providers enforce the same compliance, security, privacy, data retention limits, data deletion policies, and mandatory security update standards as the first party. Load third-party content only when the user interacts with it. Offer simple alternatives, such as linking to a form instead of embedding a widget. Serve assets such as content, icons, fonts, scripts, and widgets from infrastructure you control where practical, rather than embedding or depending on third-party services for their storage or delivery. This reduces dependency on external systems, improves reliability, and can reduce unnecessary network requests. Respect user preferences around third-party content and services. Provide clear controls to disable or opt out of non-essential third-party features.

Ensure code follows good semantic practices Use valid and standards-compliant markup. Remove optional HTML elements, attribute quotes, and default attributes if doing so does not negatively impact accessibility, readability, functionality, or performance. Include them when they improve accessibility, maintain clarity without compromising performance, or ensure consistent browser rendering. Avoid deprecated, proprietary, or non-standard technologies unless there is a clear, justified need such as legacy compatibility or accessibility. Use polyfills only when necessary and review them regularly for removal. Use standard HTML elements, attributes, features, and APIs wherever they meet the requirement. Use custom elements, Web Components, or custom functionality only when built-in web platform capabilities cannot meet the need or when building reusable design system components.

Defer the loading of non-critical resources Defer loading of non-essential external assets or set these to load asynchronously to avoid a Flash Of Unstyled Content (FOUC), Flash of Invisible Text (FOIT), or Flash of Faux Text (FOFT). Use resource and priority hints to improve loading performance when multiple assets compete for bandwidth or rendering order.

Structure metadata for machine readability Include a required title element and add optional HTML head elements where they improve usability, accessibility, or performance. Include relevant meta tags that are widely used by browsers, search engines, and other user agents. Use structured data, such as schema.org, implemented with JSON-LD, microdata, RDFa, or microformats, to enable consistent interpretation and reuse of content by both humans and machines across tools and services.

Use media queries that support sustainability goals Accommodate common user preferences using CSS media queries such as prefers-color-scheme. Account for additional preference queries, including monochrome, prefers-contrast, prefers-reduced-data, prefers-reduced-transparency, and prefers-reduced-motion where these will benefit your users. Use print and scripting media queries where they can improve efficiency or sustainability.

Ensure layouts work for different devices and requirements Use responsive and adaptive design so the product works across devices and screen sizes such as phones, tablets, laptops, desktops, TVs, and emerging platforms. Ensure the project still functions when certain features or technologies are not supported. Use progressive enhancement to enhance sustainability by starting with a baseline of HTML, then progressively improving the user experience without relying on style or interaction for core functionality, ensuring a robust and resilient project. Use carbon-aware design to reduce energy use when electricity demand or system load is high. Use situational design to replace, reduce, or disable high-impact features for lower-impact alternatives. Automated thresholds may also adjust or disable non-essential features, provided changes remain transparent. Clearly communicate what changed and why, and allow users to restore full functionality where possible. Support sustainable non-visual and indirect interaction methods such as assistive technologies, voice input, QR codes, reader view (browser, application, or RSS), and connected devices.

Use sustainable JavaScript and APIs Write JavaScript that supports long-term application performance by reducing unnecessary calculations, limiting DOM updates, and minimizing network requests. Leverage JavaScript APIs, such as Compression Streams, Page Visibility, or Vibration, when they help reduce energy use or improve efficiency. Only call client-side or server-side APIs when needed. Ensure only data required for the task is included in requests and responses.

Use dependencies sparingly and maintain them Review dependencies regularly and remove unused libraries and frameworks. Uninstall packages that are not needed. Limit the use of external libraries and frameworks to what is necessary, as this reduces the amount of code that must be downloaded and parsed by the browser. Prioritize plain code where possible. Review package size and evaluate whether individual modules can be imported instead of entire libraries, or whether a more performant alternative can be used. Do not replace established and trusted security libraries with custom implementations, as this increases vulnerability and can negatively impact sustainability. Keep all dependencies up to date through regular review and maintenance.

Include expected and beneficial files Include favicon.ico, robots.txt, opensearch.xml, site.webmanifest, and sitemap.xml by default. Include additional default files if they become standard. Include additional standard files, such as ads.txt, carbon.txt, humans.txt, and security.txt. Include additional default files if they become standard.

Use the most efficient solution for your service Choose implementation approaches that balance effort, performance, and environmental impact. Simpler solutions may reduce complexity and runtime impact but require more human effort, while prebuilt tools may reduce build time and development effort but increase ongoing resource use. Use the most performant approach for your use case. Most of the time, coding from scratch can provide the most performant results, but where a well-maintained existing solution is available it may be better optimized than what you can produce yourself. Favor native components and file systems over WYSIWYG editors, visual page builders, or heavy frameworks. Be mindful of the performance, maintenance, and environmental impact of third-party solutions. Deliver static content in place of dynamic content wherever possible. If code generation is required, favor the efficient tools, such as Static Site Generators (SSGs). Be aware that dynamic CMS-driven content typically involves greater server-side processing and relies on bulkier libraries compared to static approaches. Review plugins, extensions, and themes regularly to ensure they remain compatible with the platform and other components, efficient, and accessible. Use user interface components that are lightweight, focused, and efficient, avoiding unnecessary complexity that increases resource use, environmental impact, or maintenance burden.

Use the latest stable language version Use the latest stable version of the chosen language and framework. Use the best programming language for the task, recognizing that many tools and languages are optimized for specific types of work. Adoption effort is justified where benefits outweigh costs and there is a reasonable user base, provided it does not impact the wellbeing of those involved or become cost-prohibitive.

Reduce the number and complexity of database queries Optimize database queries to reduce load by retrieving required data in as few queries as possible, and by applying filtering and selection at the database level rather than in application or ORM code, especially for frequently accessed data. Retrieve data only once per request or process and reuse it locally instead of repeating database queries. Scope database queries to return only the fields and records that are required. Apply data lifecycle and governance controls such as Time-to-Live (TTL), use of non-sensitive identifiers like UUIDs, de-identification, and minimization of stored data in line with purpose limitation principles.

Hosting, Infrastructure, and Systems

Use sustainable hosting Include sustainability metrics when selecting and evaluating potential infrastructure, hosting, cloud, platform, externally managed content, or other digital services. Favor providers that publicly and transparently disclose their environmental policies and related performance indicators, including Power Usage Effectiveness (PUE), Water Usage Effectiveness (WUE), Carbon Usage Effectiveness (CUE), renewable energy use, emissions reduction commitments, and hardware maintenance and sourcing practices. Monitor and reduce the negative environmental impact of all running infrastructure over time. Whether external or self-hosted, track all available relevant indicators, such as energy use, water use, and server resource utilization. This includes CPU/cores, memory, storage, and network usage. Use this information to identify inefficiencies, reduce overprovisioning, optimize resource use, and support transparent sustainability reporting. Extend the lifespan of hardware. Use equipment efficiently and at the right capacity and keep it securely patched and properly maintained. New hardware should be sourced from suppliers that commit to device longevity, patching, and repair options.. Use electricity with the lowest possible carbon intensity. Hosting providers should measure and report carbon intensity using available location-based grid data, including on-site generation, backup systems, and storage. Use this information to select lower-carbon hosting providers and improve energy sourcing and infrastructure efficiency. Reduce remaining emissions using market-based carbon accounting for indirect electricity emissions under the GHG Protocol (Scope 2). When purchasing low-carbon electricity through Energy Attribute Certificates (EACs) or Renewable Energy Certificates (RECs), ensure the certificates match the time and location of the electricity used, identify when the renewable electricity was generated, can be validly issued and retired in a way that prevents double counting. Verify that the impact of domain name registration is disclosed by domain registries and registrars. Where environmental impact data is available from registrars, use it to inform domain registration decisions and mitigate environmental impact. Where such data is unavailable, assess the assumed environmental impact when making registration decisions and make sustainability-focused choices where possible.

Optimize caching and support offline access Use caching to reduce processing time and repeated database queries, API calls, and network requests. Apply server-side caching for dynamic content and client-side caching for resources that do not change frequently. Control cache lifetimes, serve static versions for stable assets, and minimize repeated requests for frequently used resources, balancing against added complexity and maintenance costs to improve how data is delivered. Keep essential content and functionality available during network interruptions. Provide offline access using web platform capabilities, such as Progressive Web Applications (PWAs), Service Workers, Web Workers, or local storage.

Reduce data transfer with compression Reduce file size before uploading images, audio, and video by using efficient formats and quality settings. Avoid applying additional compression if the file is already appropriately sized for upload. Compress media files such as images, video, and audio before uploading anywhere to reduce storage and transfer requirements.

Setup necessary error pages and redirection links Implement clear error handling and user-friendly error pages that explain what went wrong and guide users back to content. Update broken and outdated links if they are no longer valid. Use redirects only when they clearly benefit users or preserve SEO value, and avoid long or unnecessary redirect chains. Apply proportionality so engineering and maintenance costs do not outweigh performance or SEO gains. Test redirects to prevent errors and loops, and choose the simplest effective approach

Avoid maintaining unnecessary virtualized environments or containers Reduce the number of active environments by deactivating, offlining, or removing unused or redundant virtual and physical environments (e.g., containers and virtual machines) wherever this can be done without reducing required security, isolation, or compliance guarantees. Also evaluate running services in the same way. Similarly, codebases and setups for unused branches, environments, and services, and remove what is no longer needed.

Use automation wisely Automate recurring tasks such as deployment, testing, and compilation in alignment with continuous integration and continuous delivery (CI/CD) best practices to reduce manual effort and improve consistency. Favor automation tools and platforms with lower environmental impact, and avoid unnecessary duplication of automation systems. Run automated tasks only when they are needed to avoid unnecessary resource use. Use autoscaling to adjust server capacity based on demand. Implement buffering and throttling to manage load pressures. Scale resources up during high demand and scale down when demand drops to avoid overprovisioning. Restrict unwanted and unnecessary third-party crawlers, user agents, bots, and scrapers using security controls, while ensuring content remains accessible to legitimate users, search engines, and helpful or authorized crawlers. Take into account that some scrapers may be used for beneficial purposes, including informing or training large language models.

Define the frequency of data refreshes Define cache refresh rates based on user needs, accuracy requirements, and resource efficiency to determine when data is updated.

Back up critical data at routine intervals Ensure backups of systems and user data are secure and incremental to minimize storage use and reduce backup time. Limit access to backups, and establish mechanisms to prevent user-identifiable information from being stored long term. Protect backups against data loss or misuse.

Assess the impact and requirements of data processing Use carbon-aware computing to dynamically optimize workload execution by scheduling or batching tasks to run at a time when carbon intensity is lower based on real-time grid carbon intensity data, or shifting workloads to regions with lower carbon intensity when possible, while respecting security, performance, and data residency constraints. Choose communication protocols that balance user needs, security, and sustainability by improving efficiency and reducing resource use. Prioritize secure options like HTTPS and SFTP/SSH, avoid insecure legacy protocols such as HTTP and FTP, and adopt modern standards like HTTP/2 or HTTP/3 for better performance and lower network overhead. Maintain backward compatibility only where necessary. Use event-driven architecture and microservices when building products with state changes that do not require full page refreshes. Favor those where they offer a more energy-efficient alternative to REST-style synchronous APIs based on performance, power, and processing factors, and choose the approach that reduces server workload and environmental impact while meeting requirements. Avoid unnecessary data processing. Decide carefully whether processing should happen on the client or server based on performance, security, sustainability metrics, and resource use. Perform data transformations, transfers, and processing between the layers of an application as Efficient location as possible. This reduces unnecessary serialization overhead and avoids wasting resources.

Use Content Delivery Networks (CDNs) when beneficial Use a Content Delivery Network (CDN) for static content, assets, and other read-only resources only where it provides clear benefits, evaluating performance improvements and environmental impact on a case-by-case basis in line with broader web hosting choices. When serving an exclusively local audience, evaluate whether a CDN is necessary, and prefer geographically close hosting instead. Choose CDN providers that demonstrate credible, evidence-based web sustainability commitments. Avoid deploying dynamic or frequently changing resources to a CDN, as browser mechanisms like cache partitioning and cross-origin resource sharing (CORS) can limit caching benefits and interaction performance, reducing resource efficiency, while workarounds may introduce security or privacy risks.

Ensure infrastructure fits project requirements Select infrastructure that meets your requirements and customer agreements without over-provisioning. Favor standalone instances over multi-zone or distributed setups when requirements allow. Provision for average loads rather than peak loads to ensure efficient resource use.

Store data according to the needs of your users Regularly remove unused or obsolete data ("dark data") to reduce storage and energy costs, and manage whether and how long data is stored. Use classification and tagging policies to define and manage data lifecycle rules, including retention, expiration, and archival. Store data only where it provides lasting operational, analytical, or legal value and cannot be easily regenerated or replaced. Remove or archive it when it becomes obsolete. Avoid unnecessary duplication and use efficient storage practices such as compression, caching, and storage optimization techniques. Manage logs with regular rotation, retention, compression, and backup practices, including scheduling resource-intensive operations during low-activity periods where practical to reduce energy demand and operational overhead. Use resilient backup strategies, including off-site storage when necessary for resilience or recovery, and remove sensitive information from logs wherever possible to minimize security and privacy risks. Make large, long-term assets easily downloadable so users do not need repeated server requests.

Business Strategy and Product Management

Have an ethical and sustainable product strategy Develop, publish, and maintain key organizational policies such as a code of ethics, product guidelines, accessibility, and sustainability statements. Include clear language for digital products, services, and emerging or disruptive technologies, such as AI. Make these policies publicly accessible and keep them versioned for transparency. Publish web sustainability-related achievements, features, compliance updates, and other relevant information within a dedicated sustainability section. Provide evidence that sustainability policies and practices are actively implemented, monitored, and governed over time. Advocate for and comply with evidence-based legislation and standards that advance digital privacy, employment rights, transparency, accountability, responsible emerging technologies, and digital sustainability. Simultaneously make efforts to go beyond minimum expectations, especially in regard to avoiding unnecessary data collection to preserve an efficient and accessible user journey in compliance with accessibility and data protection requirements.

Assign a sustainability advocate Assign clear responsibility for digital sustainability by appointing a sustainability lead with specific digital expertise and providing them with the resources, budget, tools, and time they need to achieve their stated goals. In some organizations, expanding this into a climate working group comprising motivated individuals can add further benefits.

Inform, raise awareness, and train for sustainability Produce, provide, and/or facilitate the delivery of onboarding materials and workshops to everyone connected to your project, including internal teams, external contributors, colleagues, and organizational decision-makers. Include education on general and digital climate literacy, as well as guidance on your own sustainable technology policies. Provide active and routine training to develop, establish, and refresh sustainability skills through ongoing learning opportunities that support teams in achieving sustainability objectives. Encourage individuals to reduce their environmental impact. Share climate and sustainable initiatives and ideas. Provide resources on sustainable design, best practices, and concepts. Create and/or deliver dedicated training manuals, workshops, and materials to outline the adopted sustainability policies and practices and how to implement them. Manage and maintain these materials over time, adapting them as new policies and best practices arise. Encourage leadership, teams, and individuals to make progress toward their training goals by recognizing completion, allocating time for sustainability-related activities, and providing incentives and benefits.

Communicate the environmental impact of user choices Show users how their actions affect energy use, emissions, or resource consumption, and provide options that help them make more informed choices.

Calculate the environmental impact Conduct a life cycle assessment (LCA) to understand the environmental impact of each functional unit - a defined measure of a product or service being assessed - including lifecycle greenhouse gas (GHG) emissions and other relevant environmental impacts across the full project lifecycle. Evaluate the environmental impact of your project against comparable alternatives to inform decision-making targets. Determine whether the project's additional value or sustainability benefits justify its environmental impacts. Include the impact or estimated impact of any tooling or third-party solutions used at any stage in your pipeline. While not created by you, the emissions generated in production, maintenance, and use are also integral to your overall solution.

Define clear organizational sustainability goals and metrics Define and publish clear web sustainability goals. Identify measurable performance metrics and communicate progress against those goals so that people can understand and evaluate sustainability performance.

Validate web sustainability efforts through external verification Use independent third-party verification or assurance to validate sustainability claims. Reassess sustainability claims over time and update them when new evidence affects their accuracy.

Support mandatory disclosures and reporting Create and publish policies and practices for disclosing the environmental, social, and governance impacts of digital products, programs, and services in line with recognized standards. Publish a public sustainability impact report at least annually, including progress against previous reports and web sustainability goals. Create and maintain transparent reporting practices for the emissions and the environmental, social, and governance impacts of digital products and web services. Clearly explain how the environmental, social, and governance impacts are reduced, while avoiding misleading practices such as double counting, greenwashing, data exclusion, or selective reporting.

Create one or more impact business models Document how the organization generates revenue and how those revenue streams relate to environmental and social impacts. Describe how impacts are measured, reviewed, and improved over time.

Follow a product management and maintenance strategy Produce and maintain documentation to outline how the organization approaches product management and maintenance. Develop, implement, and maintain maintenance and security plans for all digital products and services that prioritize long-term sustainability, energy efficiency, and responsible resource use across the product lifecycle. Ensure products, prototypes, testing, and supporting processes are adequately resourced over time. Maintain sufficient staffing and budget to support ongoing maintenance, including addressing technical debt, refactoring, and evolving functionality, without abandoning projects. Include carbon and resource measurement in maintenance processes, and track improvements over time. Prioritize metrics that reflect essential value delivered and sustainability outcomes. Avoid metrics that incentivize unnecessary work, resource consumption, or emissions. Identify and document Key Failure Indicators (KFIs), including those related to accessibility, usability, and other environmental, social, and governance impacts. Monitor KFIs to detect emerging risks and inform corrective action.

Implement continuous improvement procedures Embed continuous improvement practices that clearly report what is changing, why it is changing, and whether it improves environmental sustainability outcomes. Ensure that environmental and other ESG impacts are assessed alongside operational and business performance metrics. Review deliverables and update frequently to ensure project teams have enough time to conduct user research, identify and eliminate technical debt, and produce high-quality output as well as share what they learned. Display a track record of continuous improvement (iteration) processes to analyze the digital product or service. Simultaneously address any potential consequences of ongoing experimentation, such as technical debt, product performance, and emissions. Limit analytics to strictly necessary features that aid decision-making, encouraging user feedback, and comparing performance against organization goals and user needs. Regularly review all functionality across the product lifecycle. Justify and prioritize decisions to retain, change, add, or remove features based on environmental impact, user value, usage, and maintenance cost. This includes decommissioning unused or low-traffic functionality and content.

Document updates and evolutions Provide clear, structured documentation when features are added, changed, or removed. Use a consistent versioning or change-tracking system to communicate the nature and impact of changes.

Evaluate if a digital product or service is necessary Identify whether the product or service aligns with any relevant UN Sustainable Development Goals (U.N. (SDG) and, where applicable, include corresponding targets within a sustainability statement. Evaluate whether a product or service is needed based on desirability, feasibility, and viability. Remove or reduce barriers that prevent people from using a product or service, including accessibility, technical, geographic, and fairness-related barriers.

Provide a supplier standards of practice document Apply sustainability principles across supply chain partner selection and governance, supported by clear policies for vetting and assessing potential partners. Partner with suppliers to create, track, and measure impacts on affected parties. Promote and disclose partnerships in a publicly available place, along with information on how the partnership creates a collective impact.

Share economic benefits Publicly commit to paying employees, contractors, and other affected parties a living wage. Embed incentives for affected parties such as workers and contractors into organizational practices to support impact goals, underpinned by clear policies that guide how incentives are designed and applied. Provide employee benefits that match available resources, which may include healthcare, retirement support, flexible working, and profit sharing.

Share decision-making power with affected parties Involve people, including users and staff, in decisions that impact them. Provide meaningful opportunities to participate in relevant decision-making processes and ensure decision-makers have clear authority and accountability. Where automated systems are used, provide transparency about their role in decisions, enable human oversight, and allow people to opt out, object, withdraw their consent, and challenge decisions. Ensure challenges are reviewed by a human decision-maker.

Use Diversity, Equity, Justice, Inclusion (DEJI) practices Publish clear commitments to DEIJ. Explain how the organization applies these commitments to reduce exclusion and support the long-term sustainability of access to the product for diverse and underserved or marginalized communities. Provide DEIJ training and topics such as algorithmic bias, the digital divide, employment equity, mis- and disinformation. Track and publish measurable progress in DEIJ across hiring, leadership, and operations.

Promote responsible data practices Maintain publicly accessible privacy, legal, and policy documents in plain language and accessible formats. Follow strong data protection practices aligned with recognized international standards, apply stronger protections where risks to users are higher or safeguards are insufficient, and support good practices in privacy, accessibility, and sustainability through transparent data use and governance. Respect user data rights, including access, correction, deletion, opt-out, and data portability. Provide clear user controls to manage accounts, data, and subscriptions. Only collect and retain personal data for a defined purpose and for no longer than necessary. Provide data export in open, commonly used formats. Ensure that deletion and consent changes apply across all systems, including databases, derived datasets, backups, and caches, within a reasonable timeframe. Archive and delete outdated or otherwise expired product content and data via automated expiration dates and scheduled product audits. Publish the archiving schedule, ensuring a lightweight version of the old searchable content is maintained for those that may require it.

Establish responsible practices around AI and emerging or disruptive technologies Ensure datasets used, created, or referenced by automated systems are no larger than necessary for the task, ethically sourced, screened, validated, stored, and used in a fair and non-discriminatory, responsible way. Support employees in adapting to new technologies that may change or disrupt their roles or the organization's operations. Audit and account for environmental impacts linked to the promotion or adoption of AI and emerging or disruptive technologies. This includes third-party systems and the waste, water, and emissions generated per use, as well as those resulting from initial deployment and updates. Prioritize efficiency and deployment in a way that minimizes environmental impacts. Ensure bots, crawlers, user agents, scrapers, artificial intelligence, and all other automated tools respect opt-out signals at the host, server, and site level. Providers must declare themselves as non-human within the user agent in the HTTP header. Use post-quantum encryption only where there is a clear need to protect against “harvest now, decrypt later” attacks and long-term data confidentiality risks. Treat it as supplementary to rather than replacing existing encryption methods, using both during any transition. Apply caution when adopting post-quantum encryption in high-traffic services, as the bandwidth consumption, processing demand, design complexity, and migration risks may outweigh the security benefits.

Adopt responsible financial practices Divest from fossil fuels and move financial relationships, including banking and sponsorships, toward more sustainable partners. Use responsible budgeting and financing practices that support long-term maintenance and environmental responsibility.

Adopt organizational philanthropy practices Create a corporate giving policy and establish philanthropic partnerships with strategically aligned organizations. Support voluntary and pro-bono work that helps teams learn and benefits non-profit and charitable organizations.

Plan for a digital product or service's care and end-of-life Provide clear, documented end-of-life guidelines that include data disposal, archiving, file deletion, and other relevant guidance.

Repair, reuse, refurbish, recycle or reduce e-waste Recycle, repair, or upcycle unwanted hardware and materials. Recover, redeploy, and reuse components where possible, and dispose of remaining materials in a sustainable way. Use certified repair and recycling services to handle end-of-life digital equipment and operational e-waste responsibly. Service providers should maintain a clear policy for responsible e-waste management. Maintain policies for repairing and recycling hardware and encourage repair. Prioritize reuse, refurbishment, and redeployment of existing hardware before purchasing new equipment. Allow users to repair purchased products to the best of their ability, provide replacement parts at cost where possible, and give clear instructions to help fix faults when they occur.

Define performance, environmental, and human budgets Outline and document digital sustainability budget criteria covering the full lifecycle of products and services, including creation, usage, and decommissioning. Ensure these limits are actively applied and communicated to all affected parties. Use performance budgets to cap the size and complexity of digital products or services, actively reducing data transfer and file sizes to improve performance and create more sustainable, lower-impact digital experiences. Define KPIs for engineering effort, development time, or sprints. Optimize workflows sustainably so work is done with care, while prioritizing worker health, wellbeing, and sustainable workloads. Establish baseline measurements and track improvements over time. Require that improvement claims are supported by evidence.

Use and contribute to open source Define and maintain processes for the sustainable use and contribution of open-source tools, including selection, approval, and release workflows that prioritize reuse, reduce duplication, and support long-term maintainability. Collaborate with the open-source ecosystem to support sustainable software development, grounded in open-source principles, and contribute regularly to community-based projects through code, time, or financial support to improve shared maintenance, reuse, and reduce duplication of effort.

Create a business continuity and disaster recovery plan Create, maintain, regularly review, and test incident response plans to determine readiness and ensure systems and services can quickly recover from any incident. Communicate transparently with users about incidents, service issues, and any risks to data or availability.

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