W3C API

Base URL

https://api.w3.org

Authentication

Public read endpoints require no key. Some administrative endpoints are restricted to W3C members, but nothing documented here needs credentials.

Rate limit

Not published. The dataset changes slowly, so a daily cache is more than enough.

Pricing

Free.

CORS

Enabled — callable directly from browser JavaScript

Official docs

Read the docs

Every request below was executed against the live API on 2026-08-21, and the response shown is the real body it returned — not an illustration.

curl 'https://api.w3.org/specifications?items=2'

const res = await fetch("https://api.w3.org/specifications?items=2");
if (!res.ok) throw new Error(`Request failed: ${res.status}`);
const data = await res.json();
console.log(data);

import requests

res = requests.get("https://api.w3.org/specifications?items=2", timeout=20)
res.raise_for_status()
print(res.json())

{
  "page": 1,
  "limit": 2,
  "pages": 856,
  "total": 1711,
  "_links": {
    "specifications": [
      {
        "href": "https://api.w3.org/specifications/2dcontext",
        "title": "HTML Canvas 2D Context"
      },
      {
        "href": "https://api.w3.org/specifications/2dcontext2",
        "title": "HTML Canvas 2D Context, Level 2"
      }
    ],
    "self": {
      "href": "https://api.w3.org/specifications?page=1&items=2"
    },
    "first": {
      "href": "https://api.w3.org/specifications?page=1&items=2"
    },
    "last": {
      "href": "https://api.w3.org/specifications?page=856&items=2"
    },
    "next": {
      "href": "https://api.w3.org/specifications?page=2&items=2"
    }
  }
}

page / limit / pages / totalinteger

Paging state. `total` is the full count across all pages, which listings do not otherwise reveal.

_links.specificationsarray

The items themselves, as `{href, title}` pairs. This is a HAL listing, so you must follow each `href` to get the record.

_links.self / first / last / nextobject

Navigation links. Follow `next` until it is absent rather than incrementing `page` yourself.

(specification record) shortnamestring

The stable identifier used throughout W3C, such as `css-flexbox-1`. This is the key you cache against.

(specification record) titlestring

Human-readable specification title as published.

(content type)header

`application/hal+json`. Some HTTP clients will not auto-parse this as JSON, so parse the body explicitly.

• Build a dashboard tracking which specifications have reached Recommendation
• Look up which working group owns a given specification
• Generate a reference list of standards for documentation or a compliance matrix
• Monitor a specification's publication history for new drafts
• Cross-reference browser support data against official specification status