tc39/proposal-temporal

Temporal

Provides standard objects and functions for working with dates and times.

Status

This proposal is currently Stage 4.

It will be merged into the ECMA-262 and ECMA-402 standards and this repository will be archived.

Implementation status:

• SpiderMonkey/Firefox: shipped in Firefox 139 (on 2025-05-27)
• V8/Chrome: shipped in Chrome 144 (on 2026-01-13)
• Node.js: shipped in Node 26 (on 2026-05-05)
• JavaScriptCore/Safari
• Boa
• GraalJS: planned to ship in GraalVM 25.1.0
• Kiesel

Champions

• Philipp Dunkel (@pipobscure)
• Maggie Johnson-Pint (@maggiepint)
• Matt Johnson-Pint (@mattjohnsonpint)
• Brian Terlson (@bterlson)
• Shane Carr (@sffc)
• Ujjwal Sharma (@ryzokuken)
• Philip Chimento (@ptomato)
• Jason Williams (@jasonwilliams)
• Justin Grant (@justingrant)

Overview / Motivation

Date has been a long-standing pain point in ECMAScript. This proposes Temporal, a global Object that acts as a top-level namespace (like Math), that brings a modern date/time API to the ECMAScript language. For a detailed breakdown of motivations, see: Fixing JavaScript Date

Principles:

• All Temporal objects are immutable.
• Date values can be represented in local calendar systems (why?), but they should be convertable to and from the Proleptic Gregorian Calendar.
• All time-of-day values are based on a standard 24-hour clock.
• Leap seconds are not represented.

Specification Text

The specification text can be found here.

Documentation

Reference documentation and examples can be found below.

• Temporal Documentation (English)
• Temporal のドキュメント (Japanese) (translated a part of the English document into Japanese)
• Temporal 文档 (Chinese) (translated a part of the English document into Chinese)

A cookbook to help you get started and learn the ins and outs of Temporal is available here

Polyfills

If you're working on a polyfill, please file an issue or PR so we can add yours here.

A non-production polyfill was built to validate this proposal. This polyfill continues to live in this repo, but only for the purposes of running tests and powering the documentation "playground" as described below.

DO NOT use this polyfill in your own projects! Instead, please use a polyfill from the table above.

Documentation Playground

When viewing the reference documentation, the non-production polyfill is automatically loaded in your browser, so you can try out Temporal by opening your browser's developer tools console.