Understanding Success Criterion 2.5.2: Pointer Cancellation

Success Criterion 2.5.2 Pointer Cancellation (Level A): For functionality that can be operated using a single pointer, at least one of the following is true:

No Down-Event
The down-event of the pointer is not used to execute any part of the function;
Abort or Undo
Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;
Up Reversal
The up-event reverses any outcome of the preceding down-event;
Completing the function on the down-event is essential.

Functions that emulate a keyboard or numeric keypad key press are considered essential.

This requirement applies to web content that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).


The intent of this success criterion is to make it easier for users to prevent accidental or erroneous pointer input. People with various disabilities can inadvertently initiate touch or mouse events with unwanted results.

There is a distinction between when someone touches a screen and when they remove their finger. Similarly, in mouse interaction, there is a difference between pressing and releasing the mouse button. When activation occurs only when the pointer is released, users have the opportunity to prevent (cancel) the activation. They can move their finger or other pointer (e.g., the mouse cursor) away from the target when they realise that they touched that target inadvertently or erroneously.

Up-event activation refers to the activation of a target when the pointer is released. In a touchscreen interaction, when the finger touches a target, the up-event activation ony occurs when the finger is lifted while still being within the target boundary. Similarly in mouse interaction, the up-event occurs when the mouse button is released while the cursor is still within the boundary of the initial target when the mouse button was pressed.

Authors can reduce the problem of users inadvertently triggering an action by using generic platform activation/click events that activate functionality on the up-event. For example, the "click" event in JavaScript triggers on release of the primary mouse button, and is an example of an implicit up-event. Despite its name, the onclick event handler works both for mouse interaction as well as for touch interaction.

If activation on the down-event is necessary, there are several options:

Examples of where the timing of an activation is essential and requires the down-event would be:



Related Resources

Resources are for information purposes only, no endorsement implied.


Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Sufficient Techniques

Select the situation below that matches your content. Each situation includes techniques or combinations of techniques that are known and documented to be sufficient for that situation.


Advisory Techniques

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.


The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group.

Key Terms



platform event that occurs when the trigger stimulus of a pointer is depressed

The down-event may have different names on different platforms, such as "touchstart" or "mousedown".


if removed, would fundamentally change the information or functionality of the content, and information and functionality cannot be achieved in another way that would conform


processes and outcomes achievable through user action


process or technique for achieving a result

The mechanism may be explicitly provided in the content, or may be relied upon to be provided by either the platform or by user agents, including assistive technologies.

The mechanism needs to meet all success criteria for the conformance level claimed.

single pointer


pointer input that operates with one point of contact with the screen, including single taps and clicks, double-taps and clicks, long presses, and path-based gestures



platform event that occurs when the trigger stimulus of a pointer is released

The up-event may have different names on different platforms, such as "touchend" or "mouseup".