Web IDL

Living Standard — Last Updated 8 September 2025

Participate:: GitHub whatwg/webidl (new issue, open issues); Chat on Matrix
Commits:: GitHub whatwg/webidl/commits; Snapshot as of this commit; @webidl
Tests:: web-platform-tests webidl/ (ongoing work)
Translations (non-normative):: 日本語; 简体中文; 한국어

Abstract

This standard defines an interface definition language, Web IDL, that can be used to describe interfaces that are intended to be implemented in web browsers.