temporal-polyfill

temporal-polyfill

A spec-compliant Temporal JavaScript polyfill in 16kb.

Codepen

CDN link

Browser Support

Minimum required version if...	Chrome	Edge	Safari	Safari iOS	Firefox	Node
...transpiling to target environment	36 (Jul 2014)	14 (Aug 2016)	10 (Sep 2016)	10 (Sep 2016)	52 (Mar 2017)	12 (Apr 2019)
...leaving untranspiled	60 (Jul 2017)	79 (Jan 2020)	11.1 (Mar 2018)	11.3 (Mar 2018)	55 (Aug 2017)	12 (Apr 2019)
...using BigInt features	67 (May 2018)	79 (Jan 2020)	14 (Sep 2020)	14 (Sep 2020)	68 (July 2019)	12 (Apr 2019)

BigInt Considerations

This polyfill works fine in environments without BigInt. However, without BigInt, the following will throw errors:

❌ Avoid microseconds/nanoseconds	✅ Use milliseconds instead
instant.epochMicroseconds	instant.epochMilliseconds
instant.epochNanoseconds	instant.epochMilliseconds
Temporal.Instant.fromEpochMicroseconds(micro)	Temporal.Instant.fromEpochMilliseconds(milli)
Temporal.Instant.fromEpochNanoseconds(nano)	Temporal.Instant.fromEpochMilliseconds(milli)
new Temporal.Instant(nano)	Temporal.Instant.fromEpochMilliseconds(milli)
zonedDateTime.epochMicroseconds	zonedDateTime.epochMilliseconds
zonedDateTime.epochNanoseconds	zonedDateTime.epochMilliseconds
new Temporal.ZonedDateTime(nano, tz, cal)	Temporal.Instant.fromEpochMilliseconds(milli).toZonedDateTimeISO()
	Temporal.Instant.fromEpochMilliseconds(milli).toZonedDateTime(cal)

FYI, it is not possible to properly polyfill BigInt. More Information

Installation

npm install temporal-polyfill

A) Import globally:

import 'temporal-polyfill/global'

console.log(Temporal.Now.zonedDateTimeISO().toString())

B) Import as an ES module without side effects:

import { Temporal } from 'temporal-polyfill'

console.log(Temporal.Now.zonedDateTimeISO().toString())

C) The above techniques try using the built-in Temporal object and fall back to the polyfill. To guarantee using the polyfill, do this:

import { Temporal } from 'temporal-polyfill/impl'

console.log(Temporal.Now.zonedDateTimeISO().toString())