HTML5

HTML5 is the fifth major version of the HyperText Markup Language used for structuring and presenting content on the web. Standardized by the W3C in 2014 and now maintained by WHATWG as the HTML Living Standard, HTML5 introduced semantic elements (article, section, nav, header, footer, aside), native multimedia via the audio and video elements, the canvas drawing surface, web storage (localStorage and sessionStorage), geolocation, drag-and-drop, offline application support, Web Workers for background processing, and richer form input types with built-in validation. HTML5 remains the foundation for modern web applications and the substrate that HTTP-based APIs ultimately render and consume on the client.

HTML5 is profiled on the APIs.io network. Tagged areas include Frontend, HTML5, Living Standard, Markup Language, and Multimedia.

🌐 Visit website 📡 Source on GitHub

8.1/100 minimal ▬ flat Agent 0/100 human only Full breakdown ↓
scored 2026-07-27 · rubric v0.5

0 APIs

FrontendHTML5Living StandardMarkup LanguageMultimediaSemantic WebW3CWeb DevelopmentWHATWG

Kin Score

Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5

Composite quality — 8.1/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 1.3 / 20

Commercial Clarity 0.0 / 20

Operational Transparency 0.0 / 13

Governance 0.0 / 12

Discoverability 6.8 / 10

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 15

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/html5: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

Documentation 2

Reference material describing how the API behaves

Reference

Reference

Specification

Specification

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Company 1

The organization behind the API

Website

Website

Other 1

Properties that don't map to a standard resource type

Wikipedia

Wikipedia

Source (apis.yml)

aid: html5
name: HTML5
description: HTML5 is the fifth major version of the HyperText Markup Language used for structuring and presenting content
  on the web. Standardized by the W3C in 2014 and now maintained by WHATWG as the HTML Living Standard, HTML5 introduced semantic
  elements (article, section, nav, header, footer, aside), native multimedia via the audio and video elements, the canvas
  drawing surface, web storage (localStorage and sessionStorage), geolocation, drag-and-drop, offline application support,
  Web Workers for background processing, and richer form input types with built-in validation. HTML5 remains the foundation
  for modern web applications and the substrate that HTTP-based APIs ultimately render and consume on the client.
url: https://raw.githubusercontent.com/api-evangelist/html5/refs/heads/main/apis.yml
type: Index
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/html5.png
tags:
- Frontend
- HTML5
- Living Standard
- Markup Language
- Multimedia
- Semantic Web
- W3C
- Web Development
- WHATWG
created: '2025'
modified: '2026-04-28'
specificationVersion: '0.19'
apis: []
common:
- type: DomainSecurity
  url: security/html5-domain-security.yml
- type: Website
  url: https://html.spec.whatwg.org/
- type: Reference
  url: https://developer.mozilla.org/en-US/docs/Web/HTML
- type: Specification
  url: https://www.w3.org/TR/html52/
- type: Wikipedia
  url: https://en.wikipedia.org/wiki/HTML5
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com