Which organization maintains the HTML standard today?

The WHATWG — the Web Hypertext Application Technology Working Group — maintains HTML today, having taken over from the W3C.

For years two bodies were involved: the W3C (World Wide Web Consortium) published versioned HTML standards, while the WHATWG, a group founded by browser makers, pushed a faster-moving approach. The WHATWG eventually became the single authority, and it publishes the HTML Living Standard at https://html.spec.whatwg.org/multipage/.

The phrase "living standard" is the key idea: instead of releasing fixed numbered versions (HTML 4.01, XHTML 1.0, and so on), the spec is continuously updated in place. Browsers track these changes as they happen.

• Some related topics get their own separate specifications — for example AAM (Accessibility API Mappings), ARIA (Accessible Rich Internet Applications, which adds accessibility hints), and various HTML Extensions.
• The W3C still maintains an overview page at https://www.w3.org/standards/techs/html.

Tip: people still casually say "HTML5", but technically there is no ongoing version number anymore — it is just "HTML" as a living standard.

Go deeper:

• HTML Living Standard — WHATWG — the primary source itself, continuously updated in place (note the "Last Updated" date at the top).