babel-preset-jest

30.3.0 verified Sat Apr 25 auth: no javascript

Babel preset for Jest, part of the Jest monorepo. Current version 30.3.0, released as part of Jest 30. This preset automatically configures Babel plugins needed for Jest to work with your code (e.g., transforms for ES modules, JSX, and TypeScript). Relies on @babel/core (peer dep) and babel-jest. Key differentiator: it's the official Jest preset, ensuring compatibility with Jest's internal module transformation. Actively maintained with frequent releases alongside Jest. Not to be used standalone; instead used via babel-jest or jest config.

Common errors

error Error: Requires Babel "^7.0.0-0", but was loaded with "8.0.0" ↓

cause babel-preset-jest requires @babel/core version 7 or 8 beta, but you have version 8 stable installed.

fix

Install @babel/core@^7.11.0: npm install --save-dev @babel/core@^7.11.0

error Module not found: Can't resolve 'babel-jest' ↓

cause Missing babel-jest dependency when using jest's default babel transform.

fix

Install babel-jest: npm install --save-dev babel-jest

error Jest: `babel-jest` is required for using the `.babelrc` or `babel.config.js` files. Install it: npm install --save-dev babel-jest ↓

cause babel-jest is not installed but Jest is trying to use Babel transforms.

fix

Install babel-jest: npm install --save-dev babel-jest

Warnings

breaking Jest 30 dropped support for Node 16 and 18 (prior to 18.14), requiring Node >=18.14. ↓

fix Upgrade Node to >=18.14.0

breaking Jest 30 changed the default transform from babel-jest to a new runtime, but babel-preset-jest can still be used. If you rely on automatic Babel integration, you may need to explicitly configure `transform` in jest config. ↓

fix In jest.config.js: transform: { '^.+\\.jsx?$': 'babel-jest' }

gotcha babel-preset-jest is not imported directly; it's used via Babel config string 'jest' or automatically by babel-jest. Trying to import it as a module will not work. ↓

fix Use 'jest' as a string in presets array, or rely on babel-jest.

deprecated In older Jest versions (<29), babel-preset-jest included @babel/plugin-transform-modules-commonjs by default. Starting from Jest 29, this plugin is no longer automatically added; you must install and configure it explicitly if needed. ↓

fix Install @babel/plugin-transform-modules-commonjs and add to your babel.config.js plugins array.

Install

npm install babel-preset-jest

yarn add babel-preset-jest

pnpm add babel-preset-jest

Imports

default
wrong
```
import preset from 'babel-preset-jest'
```
correct
```
// No need to import directly; configure in Jest or Babel
```
Use via babel.config.js: module.exports = { presets: ['babel-preset-jest'] } or jest config transform

createTransformer

wrong

import { createTransformer } from 'babel-preset-jest'

correct

import { createTransformer } from 'babel-jest'

createTransformer is in babel-jest, not babel-preset-jest

require presets

wrong

const preset = require('babel-preset-jest'); module.exports = { presets: [preset] }

correct

module.exports = { presets: ['jest'] }

Simply use string 'jest' in Babel config; package resolution handles it

Quickstart

Shows how to configure Jest with babel-preset-jest in Babel config and how to let babel-jest apply it automatically.

// Install: npm install --save-dev babel-preset-jest @babel/core
// In babel.config.js:
module.exports = {
  presets: ['@babel/preset-env', 'jest']
};
// Or in jest.config.js:
module.exports = {
  transform: {
    '^.+\\.jsx?$': 'babel-jest',
  },
  // The preset is automatically applied when using babel-jest
};