---
title: "Standard Assertions (@std/assert)"
description: "Common assertion functions, especially useful for testing"
jsr: jsr:@std/assert
pkg: assert
version: 1.0.19
generated: true
stability: stable
---
<!-- Autogenerated from JSR docs. Do not edit directly. -->

## Overview

<p>A library of assertion functions.
If the assertion is false an <code>AssertionError</code> will be thrown which will
result in pretty-printed diff of the failing assertion.</p>
<p>This module is browser compatible, but do not rely on good formatting of
values for AssertionError messages in browsers.</p>

```js
import { assert } from "@std/assert";

assert("I am truthy"); // Doesn't throw
assert(false); // Throws `AssertionError`
```

### Add to your project

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

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