JavaScript Temporal Instant compare()
Example
const i1 = Temporal.Instant.from("2026-05-17T14:30:00Z");
const i2 = Temporal.Instant.from("2026-05-17T14:30:00Z");
let result = Temporal.Instant.compare(i1, i2);
Try it Yourself »
Description
The compare() method returns -1, 0, or 1 indicating if the first instant
is shorter, equal to, or longer than the second.
Syntax
Temporal.Instant.compare(instant1, instant2)
Parameters
| Parameter | Description |
| instant1 | The first instant to compare. |
| instant2 | The second instant to compare. |
Return Value
| Type | Description |
| Number | -1 if instant1 is shorter than instant2. 0 if they are equal. 1 if instant1 is longer than instant2. |
Browser Support
Temporal is a major update to the JavaScript standard (TC39).
It is currently fully supported in Chrome, Edge, and Firefox, and is expected to reach full availability across browsers throughout 2026.
| Chrome 144 |
Edge 144 |
Firefox 139 |
Safari |
Opera |
| Jan 2026 | Jan 2026 | May 2025 | 🚫 | 🚫 |
Opera Support
Opera support will probably appear 1-3 browser cycles after Chromium, which often means a few months later.
Safari Support
As of March 2026, Safari has not yet announced a confirmed release date for stable support of the JavaScript Temporal API.
However, the implementation is actively in development and can be tested today in Safari Technology Preview by enabling the --use-temporal runtime flag.
Polyfill
Until Opera and Safari supports Temporal natively, use the official polyfill.
This Polyfill allows Temporal code to run in all browsers today:
Example
<script
src="https://cdn.jsdelivr.net/npm/@js-temporal/polyfill/dist/index.umd.js">
</script>
<script>
// Now you can use Temporal
const today = Temporal.Now.plainDateISO();
</script>
