Web browser specifications

This repository contains a curated list of technical Web specifications.

This list is meant to be an up-to-date input source for projects that run analyses on web technologies to create reports on test coverage, cross-references, WebIDL, quality, etc.

Table of Contents

• Installation and usage
• Upgrading

• Spec object
  • url
  • shortname
  • title
  • shortTitle
  • categories
  • standing
  • obsoletedBy
  • formerNames
  • series
    • series.shortname
    • series.currentSpecification
    • series.title
    • series.shortTitle
    • series.releaseUrl
    • series.nightlyUrl
  • seriesVersion
  • seriesComposition
  • seriesPrevious
  • seriesNext
  • forkOf
  • forks
  • organization
  • groups
  • release
    • release.url
    • release.status
    • release.filename
    • release.pages
  • nightly
    • nightly.url
    • nightly.status
    • nightly.alternateUrls
    • nightly.filename
    • nightly.pages
    • nightly.repository
    • nightly.sourcePath
  • tests
    • tests.repository
    • tests.testPaths
    • tests.excludePaths
  • source
• Spec identifiers
• How to add/update/delete a spec
• Versioning
• Spec selection criteria

Installation and usage

The list is distributed as an NPM package. To incorporate it to your project, run:

npm install web-specs

You can then retrieve the list from your Node.js program:

const specs = require("web-specs");
console.log(JSON.stringify(specs, null, 2));

Alternatively, you can fetch index.json or retrieve the list from the web-specs@latest branch.

Upgrading

The only breaking change in version 3.x is that some spec entries may not have a nightly property. This happens for specs that are not public. An example of a non public spec is an ISO standard. In such cases, the url property targets the public page that describes the spec on the standardization organization's web site. To upgrade from version 2.x to version 3.x, make sure that your code can handle specs without a nightly property.

Spec object

Each specification in the list comes with the following properties:

{
  "url": "https://www.w3.org/TR/css-color-4/",
  "seriesComposition": "full",
  "shortname": "css-color-4",
  "series": {
    "shortname": "css-color",
    "currentSpecification": "css-color-4",
    "title": "CSS Color",
    "shortTitle": "CSS Color",
    "releaseUrl": "https://www.w3.org/TR/css-color/",
    "nightlyUrl": "https://drafts.csswg.org/css-color/"
  },
  "seriesVersion": "4",
  "seriesNext": "css-color-5",
  "organization": "W3C",
  "groups": [
    {
      "name": "Cascading Style Sheets (CSS) Working Group",
      "url": "https://www.w3.org/Style/CSS/"
    }
  ],
  "release": {
    "url": "https://www.w3.org/TR/css-color-4/",
    "filename": "Overview.html"
  },
  "nightly": {
    "url": "https://drafts.csswg.org/css-color/",
    "repository": "https://github.com/w3c/csswg-drafts",
    "sourcePath": "css-color-4/Overview.bs",
    "filename": "Overview.html"
  },
  "title": "CSS Color Module Level 4",
  "source": "w3c",
  "shortTitle": "CSS Color 4",
  "categories": ["browser"],
  "tests": {
    "repository": "https://github.com/web-platform-tests/wpt",
    "testPaths": [
      "css/css-color"
    ]
  }
}

url

The versioned (but not dated) URL for the spec. For W3C specs published as TR documents, this is the TR URL. For WHATWG specs, this is the URL of the living standard. For specs developed by an organization that does not provide a public version of the spec such as ISO, this is the URL of the page that describes the spec on the organization's web site. In other cases, this is the URL of the latest Editor's Draft.

The URL should be relatively stable but may still change over time. See Spec identifiers for details.

The url property is always set.

shortname

A shortname that uniquely identifies the spec in the list. The value matches the "well-known" shortname of the spec, that usually appears in the versioned URL. For instance, for W3C specs published as TR documents, this is the TR shortname. For WHATWG specs, this is the shortname that appears at the beginning of the URL (e.g. compat for https://compat.spec.whatwg.org/). For specs developed on GitHub, this is usually the name of repository that holds the spec.

When the spec is a fork (see forkOf) of a base spec, its shortname will start with the shortname of the base spec completed by -fork- and the actual shortname of the fork spec. For instance, given an exception handling fork of the WebAssembly spec for which the raw shortname would be exception-handling, the actual spec shortname will be wasm-js-api-1-fork-exception-handling.

The shortname should be relatively stable but may still change over time. See Spec identifiers for details.

The shortname property is always set.

title

The title of the spec. The title is either retrieved from the W3C API for W3C specs, Specref or from the spec itself. The source property details the actual provenance.

The title property is always set.

shortTitle

The short title of the spec. In most cases, the short title is generated from title by dropping terms such as "Module", "Level", or "Standard". In some cases, the short title is set manually.

The shortTitle property is always set. When there is no meaningful short title, the property is set to the actual (possibly long) title of the spec.

categories

An array that contains the list of categories that the spec belongs to. The only possible value so far is "browser", which means that the spec targets web browsers.

The categories property is always set. Value may be an empty array for some of the specs in the web-specs package. Value always contains "browser" for specs in the browser-specs package.

standing

A rough approximation of whether the spec is in good standing, meaning that, regardless of its current status, it should be regarded as a spec that gets some love from targeted implementers and as a spec that has some well-defined scope, whether the spec has not yet matured enough or should only be viewed as a collection of interesting ideas for now, or whether development of the spec has been discontinued.

Specs for which the status is "Unofficial Proposal Draft" or "A Collection of Interesting Ideas" typically have a standing set to "pending" (but there may be exceptions).

Specs whose status is "Discontinued Draft" typically have a standing set to "discontinued".

The standing property is always set. Value may either be "good", "pending" or "discontinued". Value is always "good" for specs in the browser-specs package.

obsoletedBy

An array that contains the list of shortnames of specs that replace or otherwise obsolete the contents of a discontinued spec.

The obsoletedBy property is only set when standing is "discontinued", provided that there are indeed specs that replace the contents of the spec.

formerNames

An array that contains the list of shortnames that were used to identify the spec in the past. The property is not meant to provide an exhaustive list of all the shortnames that a spec ever had, but just a list of the shortnames that the spec used to have in browser-specs.

By definition, shortnames listed in formerNames properties are not current shortnames. They can be used in projects that consume the list of specs to track a specification over time.

The formerNames property is only set for specs that used to be known under a different shortname in browser-specs.

series

An object that describes the series that the spec is part of. A series includes existing levels/versions of the spec. For instance, CSS Color Module Level 4 belongs to the same series as CSS Color Module Level 3 and CSS Color Module Level 5.

Please note that the list only contains specs that are deemed to be of interest. In particular, the list does not contain levels and versions that have been fully superseded, and may not contain early drafts of new levels and versions either.

The series property is always set.

series.shortname

A shortname that uniquely identifies the series. In most cases, the shortname is the shortname of the spec without the level or version number. For instance, the series' shortname for css-color-5 is css-color. When a specification is not versioned, the series' shortname is identical to the spec's shortname.

The shortname property is always set.

series.currentSpecification

The shortname of the spec that should be regarded as the current level or version in the series. The current spec in a series is up to the group who develops the series. In most cases, the current spec is the latest level or version in the series that is a "full" spec (see seriesComposition).

The currentSpecification property is always set.

series.title

The version-less version of the title of the spec which can be used to refer to all specs in the series. The title is either retrieved from the W3C API for W3C specs, or derived from the spec's title.

The title property is always set.

series.shortTitle

The short title of the series title. In most cases, the short title is generated from series.title by dropping terms such as "Module", "Level", or "Standard". In some cases, the short title is set manually.

The shortTitle property is always set. When there is no meaningful short title, the property is set to the actual (possibly long) series title.

series.releaseUrl

The URL of the latest published snapshot for the spec series. For leveled specs (those that create a series), this matches the unversioned URL. In most cases, that unversioned URL will return the specification identified by the currentSpecification property. It may return an earlier level though, e.g. when the current specification has not yet been published as a TR document.

For instance, this property will be set to https://www.w3.org/TR/css-fonts/ for all specifications in the CSS Fonts series.

For non-leveled specs, this matches the url property.

The releaseUrl property is only set for W3C specs published as TR documents.

series.nightlyUrl

For leveled specs (those that create a series), this matches the unversioned URL that allows to access the latest Editor's Draft of the current specification in the series. That unversioned URL should return the specification identified by the currentSpecification property.

For instance, this property will be set to https://drafts.csswg.org/css-fonts/ for all specifications in the CSS Fonts series.

For specs that are not part of a series of specs, this matches the nightly.url property.

The nightlyUrl property is always set when the nightly property is set.

seriesVersion

The level or version of the spec, represented as an x, x.y or x.y.z string with x, y and z numbers, and x always greater than or equal to 1. For instance, this property will have the value 1.2 (as a string, so enclosed in ") for the WAI-ARIA 1.2 spec.

The seriesVersion property is only set for specs that have a level or version number.

seriesComposition

Whether the spec is a standalone spec, whether it is a delta spec over the previous level or version in the series, or whether it is a temporary fork of another spec. Possible values are full, delta, or fork.

The seriesComposition property is always set.

seriesPrevious

The shortname of the previous spec in the series.

The seriesPrevious property is only set where there is a previous level or version.

seriesNext

The shortname of the next spec in the series.

The seriesNext property is only set where there is a next level or version.

forkOf

The shortname of the spec that this spec is a fork of.

The forkOf property is only set when the spec is a fork of another one. The seriesComposition property is always "fork" when the forkOf property is set.

A forked specs is supposed to be temporary by nature. It will be removed from the list as soon as it gets merged into the main spec, or as soon as it gets abandoned.

forks

An array that lists shortnames of known forks of the spec in the list.

The forks property is only set when there exists at least one fork of the spec in the list, in other words when there is an entry in the list that has a forkOf property set to the spec's shortname.

organization

The name of the standardization organization that owns the spec such as W3C, WHATWG, IETF, Ecma International, Khronos Group.

The organization property is always set.

groups

The list the groups that develop (or developed) the spec. Each item in the array is an object with a name property that contains the human-readable name of the group and a url property that targets the homepage of the group.

The groups property is always set. In most cases, a spec is developed by one and only one group.

release

An object that represents the latest published snapshot of the spec, when it exists.

The release property is only set for W3C specs published as TR documents.

release.url

The URL of the latest published snapshot of the spec. Matches the versioned URL (see url).

The url property is always set.

release.status

The status of the latest published snapshot of the spec. See Documents published at W3C for possible values, e.g. "Recommendation", "Candidate Recommendation Draft", "Draft Registry" or "Working Draft".

The status property is always set.

release.filename

The filename of the resource that gets served when the default URL is fetched. For instance, the filename for https://www.w3.org/TR/presentation-api/ is Overview.html, meaning that the specification could also be retrieved from https://www.w3.org/TR/presentation-api/Overview.html. The filename may be useful to distinguish links to self in a spec.

The filename property is always set.

release.pages

The list of absolute page URLs when the spec is a multipage spec.

The pages property is only set for specs identified as multipage specs.

nightly

An object that represents the latest Editor's Draft of the spec, or the living standard when the concept of Editor's Draft does not exist.

The nightly property is always set unless the spec does not have a public version available through a URL. For instance, ISO specs are not publicly available.

nightly.url

The URL of the latest Editor's Draft or of the living standard.

The URL is either retrieved from the W3C API for W3C specs, or Specref. The document at the versioned URL is considered to be the latest Editor's Draft if the spec does neither exist in the W3C API nor in Specref. The source property details the actual provenance.

The URL should be relatively stable but may still change over time. See Spec identifiers for details.

The url property is always set.

nightly.status

The status of the nightly version of the spec. This is typically "Editor's Draft" or "Living Standard", but can also be "Draft Community Group Report" for Community Group drafts, "Unofficial Proposal Draft" for some unofficial CSS specifications, "Internet Standard" for IETF specifications, etc.

The status property is always set.

nightly.alternateUrls

A list of alternate URLs for the Editor's Draft or the living standard.

The list typically contains URLs that external sources may use to reference the spec, be it because the canonical URL evolved over time and sources still use old URLs (e.g. when the spec was incubated in a Community Group and transitioned to a Working Group), or because the canonical URL is unstable for some reason and external sources decided to use a workaround (e.g. CSS drafts).

Alternate URLs should only be used to ease mapping between external sources and specs in browser-specs. The canonical URL in nightly.url should be preferred to reference a spec otherwise.

Alternate URLs are only set when needed, in other words when an alternate URL is effectively in use in some external source and when the external source cannot easily be updated to use the canonical URL. In particular, the list is not meant to be exhaustive.

The alternateUrls property is always set and is often an empty array.

nightly.filename

The filename of the resource that gets served when the default URL is fetched. For instance, the filename for https://w3c.github.io/presentation-api/ is index.html, meaning that the specification could also be retrieved from https://w3c.github.io/presentation-api/index.html. The filename may be useful to distinguish links to self in a spec.

The filename property is always set.

nightly.pages

The list of absolute page URLs when the spec is a multipage spec.

The pages property is only set for specs identified as multipage specs.

nightly.repository

The URL of the repository that contains the source of the Editor's Draft or of the living standard.

The URL is either retrieved from the Specref or computed from nightly.url.

The repository property is always set except for IETF specs where such a repo does not always exist.

nightly.sourcePath

The relative path to the filename that contains the source of the Editor's Draft or of the living standard at the HEAD of the default branch of the repository.

That path is computed by parsing the contents of the repository for common patterns. The info must be specified in specs.json for specifications that do not follow a common pattern.

The sourcePath property is always set when repository is set... except in rare cases where the source of the spec is not in the default branch of the repository.

Note: The path is relative to the root of the repository, and only valid in the default branch of the repository. If needed, the source may be fetched from the absolute HTTPS URL ${nightly.repository}/blob/HEAD/${nightly.sourcePath}.

tests

An object that links the specification with its test suite when it has one.

tests.repository

The URL of the repository that contains the test suite of the specification, typically https://github.com/web-platform-tests/wpt.

The repository property is always set when the tests object is present.

tests.testPaths

The list of relative paths to the actual tests at the HEAD of the default branch of the test repository.

For test suites within Web Platform Tests, the list is determined by looking at META.yml files within each folder.

The testPaths array typically only contains one entry, but tests of a given spec are sometimes spread over multiple folders. For instance, that is the case for DOM and HTML tests.

The testPaths property is usually set when the tests object is present. When absent, that means that the entire repository is the test suite.

tests.excludePaths

The list of relative sub-paths of paths listed in the testPaths property that do not contain tests for the underlying spec. For instance, tests for the WebXR Device API are under the webxr folder, but several folders under webxr actually contain test suites for WebXR module specs and as such need to be excluded from the test suite of the WebXR Device API spec.

The excludePaths property is seldom set.

source

The provenance for the title and nightly property values. Can be one of:

• w3c: information retrieved from the W3C API
• specref: information retrieved from Specref
• ietf: information retrieved from the IETF datatracker
• spec: information retrieved from the spec itself

The source property is always set.

Spec identifiers

An entry in browser-specs contains properties that can be viewed as identifiers: shortname, url, and nightly.url. Please note that these identifiers are not fully stable.

The shortname property should remain mostly stable over time. The shortname may still change though, for instance when a W3C specification starts being published as a TR document with a shortname that is different from the one used during incubation, or when an IETF specification gets published as an RFC. Starting in July 2023, when the shortname of a specification changes in browser-specs, the previous shortname gets added to a formerNames property. This makes it possible to track a specification entry over time in browser-specs.

The url property contains a URL of the specification that can be regarded as canonical and mostly stable too, but that URL will typically change when a specification starts getting published as a formal technical document, or when a specification transitions from one organization or group to another one.

The nightly.url property is the least stable identifier of a specification. That URL may be under the control of an individual or group, who may decide to change the URL at any time. Or it may be affected by a change of status. For instance, the nightly.url property will change when a W3C spec incubated in the Web Platform Incubator Community Group (WICG) transitions to a Working Group, or when a new version of an IETF draft gets published.

If your project tracks specifications over time and relies on browser-specs to gather information about these specifications, you will need to record the shortname of the specifications you're tracking, and apply the following algorithm to find the relevant specification entry in browser-specs:

1. Look for an entry in browser-specs whose shortname matches the recorded shortname. If one is found, that is the relevant specification entry.
2. Look for entries in browser-specs that have the recorded shortname in its formerNames property. If one is found, that is the relevant specification entry.
3. If you found more than one entry in the previous step, that looks like a bug in browser-specs, please raise an issue.
4. If you're still looking for a relevant specification entry at this point whereas the recorded shortname used to exist in browser-specs, that looks like a bug in browser-specs too, please raise an issue.

Shortname changes may occur in major and minor releases of npm packages but not in patch releases.

How to add/update/delete a spec

If you believe that a spec should be added to the list, check the selection criteria below and use the "New spec" issue template.

For other types of changes, please check contributing instructions.

Spec selection criteria

This repository contains a curated list of technical Web specifications that are deemed relevant for the Web platform. Roughly speaking, this list should match the list of web specs actively developed by W3C, the WHATWG and a few other organizations.

To try to make things more concrete, the following criteria are used to assess whether a spec should a priori appear in the list:

1. The spec is stable or in development. Superseded and abandoned specs will not appear in the list. For instance, the list contains the HTML LS spec, but not HTML 4.01 or HTML 5).
2. The spec is being developed by a well-known standardization or pre-standardization group. Today, this means a W3C Working Group or Community Group, the WHATWG, the IETF, the TC39 group, the Khronos Group, the Alliance for Open Media (AOM), or ISO.
3. The spec sits at the application layer or is "close to it". For instance, most IETF specs are likely out of scope, but some that are exposed to Web developers are in scope.
4. The spec defines normative content (terms, CSS, IDL), or it contains informative content that other specs often need to refer to (e.g. guidelines from horizontal activities such as accessibility, internationalization, privacy and security).

There are and there will be exceptions to the rule. Besides, some of these criteria remain fuzzy and/or arbitrary, and we expect them to evolve over time, typically driven by needs expressed by projects that may want to use the list.

Versioning

This project adheres to Semantic Versioning with the following increment rules given a major.minor.patch version:

• major: A property disappeared, its meaning has changed, or some other incompatible API change was made. When the major number gets incremented, code that parses the list likely needs to be updated.
• minor: A new property was added, the list of specs changed (a new spec added, or a spec was removed). Code that parses the list should continue to work undisturbed, but please note that there is no guarantee that a spec that was present in the previous version will continue to appear in the new version. Situations where a spec gets dropped should remain scarce. If you believe that removal of a spec should rather trigger a major update, please raise an issue and explain how it affects your project.
• patch: Info about one or more specs changed. Minor updates were made to the code that don't affect the list.

Spec selection criteria

This repository contains a curated list of technical Web specifications that are deemed relevant for the Web platform. Roughly speaking, this list should match the list of web specs actively developed by W3C, the WHATWG and a few other organizations.

To try to make things more concrete, the following criteria are used to assess whether a spec should a priori appear in the list:

1. The spec is stable or in development. Superseded and abandoned specs will not appear in the list. For instance, the list contains the HTML LS spec, but not HTML 4.01 or HTML 5).
2. The spec is being developed by a well-known standardization or pre-standardization group. Today, this means a W3C Working Group or Community Group, the WHATWG, the IETF, the TC39 group or the Khronos Group.
3. The spec sits at the application layer or is "close to it". For instance, most IETF specs are likely out of scope, but some that are exposed to Web developers are in scope.
4. The spec defines normative content (terms, CSS, IDL), or it contains informative content that other specs often need to refer to (e.g. guidelines from horizontal activities such as accessibility, internationalization, privacy and security).

There are and there will be exceptions to the rule. Besides, some of these criteria remain fuzzy and/or arbitrary, and we expect them to evolve over time, typically driven by needs expressed by projects that may want to use the list.