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---
title: How to set up Vitest with Next.js
nav_title: Vitest
description: Learn how to set up Vitest with Next.js for Unit Testing.
---

Vite and React Testing Library are frequently used together for **Unit Testing**. This guide will show you how to setup Vitest with Next.js and write your first tests.

> **Good to know:** Since `async` Server Components are new to the React ecosystem, Vitest currently does not support them. While you can still run **unit tests** for synchronous Server and Client Components, we recommend using **E2E tests** for `async` components.

## Quickstart

You can use `create-next-app` with the Next.js [with-vitest](https://github.com/vercel/next.js/tree/canary/examples/with-vitest) example to quickly get started:

```bash filename="Terminal"
npx create-next-app@latest --example with-vitest with-vitest-app
```

## Manual Setup

To manually set up Vitest, install `vitest` and the following packages as dev dependencies:

```bash filename="Terminal"
# Using TypeScript
npm install -D vitest @vitejs/plugin-react jsdom @testing-library/react @testing-library/dom vite-tsconfig-paths
# Using JavaScript
npm install -D vitest @vitejs/plugin-react jsdom @testing-library/react @testing-library/dom
```

Create a `vitest.config.mts|js` file in the root of your project, and add the following options:

```ts filename="vitest.config.mts" switcher
import { defineConfig } from 'vitest/config'
import react from '@vitejs/plugin-react'
import tsconfigPaths from 'vite-tsconfig-paths'

export default defineConfig({
  plugins: [tsconfigPaths(), react()],
  test: {
    environment: 'jsdom',
  },
})
```

```js filename="vitest.config.js" switcher
import { defineConfig } from 'vitest/config'
import react from '@vitejs/plugin-react'

export default defineConfig({
  plugins: [react()],
  test: {
    environment: 'jsdom',
  },
})
```

For more information on configuring Vitest, please refer to the [Vitest Configuration](https://vitest.dev/config/#configuration) docs.

Then, add a `test` script to your `package.json`:

```json filename="package.json"
{
  "scripts": {
    "dev": "next dev",
    "build": "next build",
    "start": "next start",
    "test": "vitest"
  }
}
```

When you run `npm run test`, Vitest will **watch** for changes in your project by default.

## Creating your first Vitest Unit Test

Check that everything is working by creating a test to check if the `<Page />` component successfully renders a heading:

<AppOnly>

```tsx filename="app/page.tsx" switcher
import Link from 'next/link'

export default function Page() {
  return (
    <div>
      <h1>Home</h1>
      <Link href="/about">About</Link>
    </div>
  )
}
```

```jsx filename="app/page.jsx" switcher
import Link from 'next/link'

export default function Page() {
  return (
    <div>
      <h1>Home</h1>
      <Link href="/about">About</Link>
    </div>
  )
}
```

```tsx filename="__tests__/page.test.tsx" switcher
import { expect, test } from 'vitest'
import { render, screen } from '@testing-library/react'
import Page from '../app/page'

test('Page', () => {
  render(<Page />)
  expect(screen.getByRole('heading', { level: 1, name: 'Home' })).toBeDefined()
})
```

```jsx filename="__tests__/page.test.jsx" switcher
import { expect, test } from 'vitest'
import { render, screen } from '@testing-library/react'
import Page from '../app/page'

test('Page', () => {
  render(<Page />)
  expect(screen.getByRole('heading', { level: 1, name: 'Home' })).toBeDefined()
})
```

> **Good to know**: The example above uses the common `__tests__` convention, but test files can also be colocated inside the `app` router.

</AppOnly>

<PagesOnly>

```tsx filename="pages/index.tsx" switcher
import Link from 'next/link'

export default function Page() {
  return (
    <div>
      <h1>Home</h1>
      <Link href="/about">About</Link>
    </div>
  )
}
```

```jsx filename="pages/index.jsx" switcher
import Link from 'next/link'

export default function Page() {
  return (
    <div>
      <h1>Home</h1>
      <Link href="/about">About</Link>
    </div>
  )
}
```

```tsx filename="__tests__/index.test.tsx" switcher
import { expect, test } from 'vitest'
import { render, screen } from '@testing-library/react'
import Page from '../pages/index'

test('Page', () => {
  render(<Page />)
  expect(screen.getByRole('heading', { level: 1, name: 'Home' })).toBeDefined()
})
```

```jsx filename="__tests__/index.test.jsx" switcher
import { expect, test } from 'vitest'
import { render, screen } from '@testing-library/react'
import Page from '../pages/index'

test('Page', () => {
  render(<Page />)
  expect(screen.getByRole('heading', { level: 1, name: 'Home' })).toBeDefined()
})
```

</PagesOnly>

## Running your tests

Then, run the following command to run your tests:

```bash filename="Terminal"
npm run test
# or
yarn test
# or
pnpm test
# or
bun test
```

## Additional Resources

You may find these resources helpful:

- [Next.js with Vitest example](https://github.com/vercel/next.js/tree/canary/examples/with-vitest)
- [Vitest Docs](https://vitest.dev/guide/)
- [React Testing Library Docs](https://testing-library.com/docs/react-testing-library/intro/)