---
title: "@std/datetime"
description: "Utilities for dealing with Date objects"
jsr: jsr:@std/datetime
pkg: datetime
version: 0.225.7
generated: true
stability: unstable
---
<!-- Autogenerated from JSR docs. Do not edit directly. -->

:::info Unstable

This @std package is experimental and its API may change without a major version bump.

:::
## Overview

<p>Utilities for dealing with <a href="https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Date" rel="nofollow"><code>Date</code></a> objects.</p>

```js
import { dayOfYear, isLeap, difference, HOUR, MINUTE, SECOND } from "@std/datetime";
import { assertEquals } from "@std/assert";

assertEquals(dayOfYear(new Date("2019-03-11T03:24:00")), 70);
assertEquals(isLeap(1970), false);

const date0 = new Date("2018-05-14");
const date1 = new Date("2020-05-13");
assertEquals(difference(date0, date1).years, 1);

assertEquals(HOUR / MINUTE, 60);
assertEquals(MINUTE / SECOND, 60);
```

### Add to your project

```sh
deno add jsr:@std/datetime
```

<a href="https://jsr.io/@std/datetime/doc" class="docs-cta jsr-cta">See all symbols in @std/datetime on
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