N-Triples is a line-based, plain text format for encoding an RDF graph.

RDF 1.2 N-Triples introduces triple terms as a fourth kind of RDF term which can be used as the subject or object of another triple, making it possible to make statements about other statements. RDF 1.2 N-Triples also adds support for directional language-tagged strings.

This document is part of the RDF 1.2 document suite. The N-Triples format is a line-based RDF syntax based on a subset of Turtle [[RDF12-TURTLE]].


This document defines N-Triples, a concrete syntax for RDF [[RDF12-CONCEPTS]]. N-Triples is an easy to parse line-based subset of Turtle [[RDF12-TURTLE]].

The syntax is a revised version of N-Triples as originally defined in the RDF Test Cases [[RDF-TESTCASES]] document. Its original intent was for writing test cases, but it has proven to be popular as an exchange format for RDF data.

An N-Triples document contains no parsing directives.

N-Triples triples are a sequence of RDF terms representing the subject, predicate, and object of an RDF Triple. These may be separated by white space (spaces, and/or tabs). This sequence is terminated by a . (optionally followed by white space and/or a comment), and a new line (optional at the end of a document).


N-Triples triples are also Turtle simple triples, but Turtle includes other representations of RDF terms and abbreviations of RDF Triples. When parsed by a Turtle parser, data in the N-Triples format will produce exactly the same triples as a parser for the N-Triples language.

The RDF graph represented by an N-Triples document contains exactly each triple matching the N-Triples triple production.

N-Triples Language

An N-Triples document allows writing down an RDF graph in a textual form. An RDF graph is made up of simple triples consisting of a subject, predicate, and object and optional blank lines. Comments may be given after a # that is not part of another lexical token and continue to the end of the line.

Simple Triples

The simplest triple statement is a sequence of (subject, predicate, and object) terms, and terminated by .. White space (spaces U+0020 or tabs U+0009) may surround terms, except where significant as noted in the grammar.

Comments are treated as white space, and may be given after a # that is not part of another lexical token and continue to the end of the line.


Triple Terms

A triple term may be the object of an RDF triple.

A triple term is represented as a tripleTerm with subject, predicate, and object preceded by <<, and followed by >>. Note that triple terms may be nested.



IRIs may be written only as resolved IRIs. IRIs are preceded by < and followed by >, and may contain numeric escape sequences (described below). For example <http://example.org/#green-goblin>.

RDF Literals

Literals are used to identify values such as strings, numbers, dates.

Literals (Grammar production Literal) have a lexical form followed by either a language tag (possibly including base direction), a datatype IRI, or neither.

The representation of the lexical form consists of an initial delimiter ", a sequence of permitted characters or numeric escape sequence or string escape sequence, and a final delimiter.

Literals may not contain the characters ", LF, or CR except in their escaped forms. In addition \ may not appear in any quoted literal except as part of an escape sequence and a " character can only be included in a quoted literal using an escape sequence.

The corresponding lexical form is the characters between the delimiters, after processing any escape sequences. If present, the LANG_DIR terminal matches the language tag and optionally the base direction. The language tag is preceded by an @, and, if present, the base direction is separated from the language tag by --. If there is no language tag, there may be a datatype IRI, preceded by ^^. If there is no datatype IRI and no language tag, then it is a simple literal and the datatype is http://www.w3.org/2001/XMLSchema#string.


RDF Blank Nodes

As in N-Triples, RDF blank nodes are expressed as _: followed by a blank node label which is a series of name characters. The characters in the label are built upon PN_CHARS_BASE, liberalized as follows:

A fresh RDF blank node is allocated for each unique blank node identifier in a document. Repeated use of the same blank node identifier identifies the same blank node.


A Canonical form of N-Triples

This section defines a canonical form of N-Triples which has a completely specified layout. The grammar for the language is unchanged.

While the N-Triples syntax allows choices for the representation and layout of RDF data, the canonical form of N-Triples provides a unique syntactic representation of any triple. Each code point can be represented by only one of UCHAR, ECHAR, or unencoded character, where the relevant production allows for a choice in representation. Each triple is represented entirely on a single line with specified white space.

Canonical N-Triples has the following additional constraints on layout:

This specification defines conformance criteria for:

A conforming N-Triples document is an RDF string that conforms to the grammar and additional constraints defined in , starting with the ntriplesDoc production. An N-Triples document serializes an RDF graph.

A conforming Canonical N-Triples document is an N-Triples document that follows the additional constraints of Canonical N-Triples.

A conforming N-Triples parser is a system capable of reading N-Triples documents on behalf of an application. It makes the serialized RDF graph, as defined in , available to the application, usually through some form of API.

The IRI that identifies the N-Triples language is: http://www.w3.org/ns/formats/N-Triples

Media Type and Content Encoding

The media type of N-Triples is application/n-triples. The content encoding of N-Triples is always UTF-8. See N-Triples Media Type for the media type registration form.

Other Media Types

N-Triples has been historically provided with other media types. N-Triples may also be provided as text/plain. When used in this way N-Triples MUST use the escaped form of any character outside US-ASCII. As N-Triples is a subset of Turtle an N-Triples document MAY also be provided as text/turtle. In both of these cases the document is not an N-Triples document as an N-Triples document is only provided as application/n-triples.

N-Triples Grammar

An N-Triples document is an RDF string encoded in UTF-8 [[!RFC3629]].

White Space

White space (spaces, and/or tabs) is allowed outside of terminals. Rule names below in capitals indicate where white space is significant.

White space is significant in the production STRING_LITERAL_QUOTE.

A blank line, consisting of only white space and/or a comment, may appear wherever a triple production is allowed, and are treated as white space.

N-Triples allows only horizontal white space (spaces or tabs) as compared to Turtle [[RDF12-TURTLE]] which also treats LF and CR as white space.


Comments in N-Triples start at # outside an IRIREF or STRING_LITERAL_QUOTE, and continue to the end of line — marked by character CR or LF — or to the end of file, if there is no end of line after the comment marker. Comments are treated as white space.


The EBNF used here is defined in XML 1.0 [[EBNF-NOTATION]].

Escape sequence rules are the same as Turtle [[RDF12-TURTLE]]. However, as only the STRING_LITERAL_QUOTE production is allowed new lines in literals MUST be escaped.

Selected Terminal Literal Strings

This document uses some specific terminal literal strings [[EBNF-NOTATION]]. To clarify the Unicode code points used for these terminal literal strings, the following table describes specific characters and sequences used throughout this document.

U+0008 BS Backspace
U+0009 HT Horizontal tab
U+000A LF Line feed
U+000B VT Vertical tab
U+000C FF Form feed
U+000D CR Carriage return
U+0022 " Quotation mark
U+0023 # Number sign
U+002D - Hyphen
U+002E . Full stop
U+0030 0 Digit zero
U+0039 9 Digit nine
U+003B : Colon
U+003C < Less-than sign
U+003E > Greater-than sign
U+0040 @ At sign
U+0041 A Latin capital letter A
U+0046 F Latin capital letter F
U+005C \ Backslash
U+005F _ Underscore
U+0061 a Latin small letter A
U+007A F Latin small letter Z
U+007F DEL Delete
U+00B7 · Middle dot
U+203F Undertie
U+2040 Character tie

Other short terminal literal strings are composed of specific sequences of Unicode characters:

two concatenated less-than sign characters, each having the code point U+003C
two concatenated greater-than sign characters, each having the code point U+003E
two concatenated circumflex accent characters, each having the code point U+005E
_ followed by :
two concatenated - characters


Parsing N-Triples requires a state of one item:

RDF Term Constructors

This table maps productions and lexical tokens to RDF terms or components of RDF terms listed in :

BLANK_NODE_LABEL blank node The string after _:, is a key in bnodeLabels. If there is no corresponding blank node in the map, one is allocated.
IRIREF IRI The characters between < and > are taken, with escape sequences unescaped, to form the IRI.
LANG_DIR language tag The characters following the @ form the language tag and optionally the base direction, if the matched characters include --.
STRING_LITERAL_QUOTE lexical form The characters between the outermost quotation marks (") are taken, with escape sequences unescaped, to form the string of a lexical form.
literal literal The literal has a lexical form of the first rule argument, STRING_LITERAL_QUOTE, and either a language tag with optional base direction from LANG_DIR or a datatype IRI of iri, depending on which rule matched the input. If the LANG_DIR rule matched, the language tag and base direction are taken from LANG_DIR. If there is no base direction, the datatype is rdf:langString. If there is a base direction, the datatype is rdf:dirLangString. If neither LANG_DIR nor datatype IRI match, the literal has a datatype of xsd:string.
tripleTerm triple term The triple term is composed of the terms constructed from the subject, predicate, and object productions.

RDF Triple Construction

An N-Triples document defines an RDF graphs composed of a set of RDF Triples. The triple production produces a triple defined by the terms constructed for subject, predicate, and object.

Privacy Considerations

The N-Triples format is used to express arbitrary application data, which may include the expression of personally identifiable information (PII) or other information which could be considered sensitive. Authors publishing such information are advised to carefully consider the needs and use of publishing such information, as well as the applicable regulations for the regions where the data is expected to be consumed and potentially revealed (e.g., GDPR, CCPA, others), particularly whether authorization measures are needed for access to the data.

Security Considerations

The STRING_LITERAL_QUOTE production allows the use of unescaped control characters. Although this specification does not directly expose this content to an end user, it might be presented through a user agent, which may cause the presented text to be obfuscated due to presentation of such characters.

N-Triples is a general-purpose assertion language; applications may evaluate given data to infer more assertions or to dereference IRIs, invoking the security considerations of the scheme for that IRI. Note in particular, the privacy issues in [[RFC3023]] section 10 for HTTP IRIs. Data obtained from an inaccurate or malicious data source may lead to inaccurate or misleading conclusions, as well as the dereferencing of unintended IRIs. Care must be taken to align the trust in consulted resources with the sensitivity of the intended use of the data; inferences of potential medical treatments would likely require different trust than inferences for trip planning.

The N-Triples language is used to express arbitrary application data; security considerations will vary by domain of use. Security tools and protocols applicable to text (for example, PGP encryption, checksum validation, password-protected compression) may also be used on N-Triples documents. Security/privacy protocols must be imposed which reflect the sensitivity of the embedded information.

N-Triples can express data which is presented to the user, such as RDF Schema labels. Applications rendering strings retrieved from untrusted N-Triples documents, or using unescaped characters, SHOULD use warnings and other appropriate means to limit the possibility that malignant strings might be used to mislead the reader. The security considerations in the media type registration for XML ([[RFC3023]] section 10) provide additional guidance around the expression of arbitrary data and markup.

N-Triples uses IRIs as term identifiers. Applications interpreting data expressed in N-Triples SHOULD address the security issues of [[[RFC3987]]] [[RFC3987]] Section 8, as well as [[[RFC3986]]] [[RFC3986]] Section 7.

Multiple IRIs may have the same appearance. Characters in different scripts may look similar (for instance, a Cyrillic "о" may appear similar to a Latin "o"). A character followed by combining characters may have the same visual representation as another character (for example, LATIN SMALL LETTER "E" followed by COMBINING ACUTE ACCENT has the same visual representation as LATIN SMALL LETTER "E" WITH ACUTE). Any person or application that is writing or interpreting data in N-Triples must take care to use the IRI that matches the intended semantics, and avoid IRIs that may look similar. Further information about matching visually similar characters can be found in [[[UNICODE-SECURITY]]] [[UNICODE-SECURITY]] and [[[RFC3987]]] [[RFC3987]] Section 8.

N-Triples Internet Media Type, File Extension and Macintosh File Type

Eric Prud'hommeaux
See also:
How to Register a Media Type for a W3C Specification
Internet Media Type registration, consistency of use
TAG Finding 3 June 2002 (Revised 4 September 2002)

The Internet Media Type (formerly known as MIME Type) for N-Triples is "application/n-triples".

It is recommended that N-Triples files have the extension ".nt" (all lowercase) on all platforms.

It is recommended that N-Triples files stored on Macintosh HFS file systems be given a file type of "TEXT".

This information that follows will be submitted to the IESG for review, approval, and registration with IANA.

Type name:
Subtype name:
Required parameters:
Optional parameters:
Encoding considerations:
The syntax of N-Triples is expressed over code points in Unicode [[UNICODE]]. The encoding is always UTF-8 [[UTF-8]].
Unicode code points may also be expressed using an \uXXXX (U+0 to U+FFFF) or \UXXXXXXXX syntax (for U+10000 onwards) where X is a hexadecimal digit [0-9A-F]
Security considerations:
See .
Interoperability considerations:
There are no known interoperability issues.
Published specification:
This specification.
Applications which use this media type:
No widely deployed applications are known to use this media type. It may be used by some web services and clients consuming their data.
Additional information:
Magic number(s):
File extension(s):
Macintosh file type code(s):
Person & email address to contact for further information:
Eric Prud'hommeaux <eric@w3.org>
Intended usage:
Restrictions on usage:
Author/Change controller:
The N-Triples specification is the product of the RDF WG. The W3C reserves change control over this specifications.


Acknowledgments for RDF 1.1

The editor of the RDF 1.1 edition acknowledges valuable contributions from Gregg Kellogg, Eric Prud'hommeaux, Dave Beckett, David Robillard, Gregory Williams, Pat Hayes, Richard Cyganiak, Henry S. Thompson, Peter Ansell, Evan Patton and David Booth.

This specification is a product of extended deliberations by the members of the RDF Working Group. It draws upon the earlier specification in [[RDF-TESTCASES]], edited by Dave Beckett.

Acknowledgments for RDF 1.2

The editors of the RDF 1.2 edition acknowledge valuable contributions from Andy Seaborne.

In addition to the editors, the following people have contributed to this specification:

Recognize members of the Task Force? Not an easy to find list of contributors.

Changes between RDF 1.1 and RDF 1.2