# Is ts-jest ESM-only? Can you require() it?

> ts-jest@29.4.12 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

A Jest transformer with source map support that lets you use Jest to test projects written in TypeScript

Last verified Sep 9, 2026 against ts-jest@29.4.12.

ts-jest ships CommonJS only. require("ts-jest") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.15.0 || ^16.10.0 || ^18.0.0 || >=20.0.0. import "ts-jest" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

## What to do

1. require("ts-jest") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.15.0 || ^16.10.0 || ^18.0.0 || >=20.0.0.
2. From ES modules use the default import: import tsJest from "ts-jest"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 29.4.12 (Jul 22, 2026)
- Module format: CommonJS
- Last CommonJS version: 29.4.12
- TypeScript types: bundled
- Node engines: ^14.15.0 || ^16.10.0 || ^18.0.0 || >=20.0.0
- Weekly downloads: 24.2M
- License: MIT

## Runtime test results for ts-jest@29.4.12

Installed and executed on Sep 9, 2026 with require("ts-jest") from a CommonJS file and import "ts-jest" from an ES module.

| Runtime | require("ts-jest") | import "ts-jest" |
|---|---|---|
| Node.js 18 | works | works |
| Node.js 20 | works | works |
| Node.js 22 | works | works |
| Node.js 24 | works | works |
| Node.js 26 | works | works |
| Bun 1.4.0 | works | works |

## How to import ts-jest

ES modules:

```js
import tsJest from "ts-jest";
```

CommonJS:

```js
const tsJest = require("ts-jest");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (184 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 27.0.0 – 29.4.12 | CommonJS | May 25, 2021 |

## Frequently asked

**Is ts-jest ESM-only?**

ts-jest@29.4.12 is a CommonJS package. ts-jest ships CommonJS only. require("ts-jest") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js ^14.15.0 || ^16.10.0 || ^18.0.0 || >=20.0.0. import "ts-jest" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

**Can I import ts-jest with ES module syntax?**

Yes. import tsJest from "ts-jest" works in Node.js and Bun because they support importing CommonJS modules. Named imports work only when Node.js can statically detect the exports.

**Does ts-jest work in Bun?**

Yes. import "ts-jest" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does ts-jest ship TypeScript types?**

Yes. ts-jest bundles its own type declarations; no @types package is needed.

## Links

- [ts-jest on npm](https://www.npmjs.com/package/ts-jest)
- [Source repository](https://github.com/kulshekhar/ts-jest)
- [HTML version](https://canirequire.com/package/ts-jest/)
- [JSON version](https://canirequire.com/package/ts-jest.json)

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