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

> terser@5.51.2 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

JavaScript parser, mangler/compressor and beautifier toolkit for ES6+

Last verified Sep 9, 2026 against terser@5.51.2.

terser publishes both a CommonJS entry and a native ESM entry (ESM added in 5.0.0). require("terser") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=10. import "terser" works alongside it.

## What to do

1. Nothing to change. require("terser") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=10. import * as terser from "terser" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 5.51.2 (Aug 27, 2026)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 5.51.2
- Native ESM since: 5.0.0
- TypeScript types: bundled
- Node engines: >=10
- Weekly downloads: 71.8M
- License: BSD-2-Clause

## Runtime test results for terser@5.51.2

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

| Runtime | require("terser") | import "terser" |
|---|---|---|
| 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 terser

ES modules:

```js
import * as terser from "terser";
```

Namespace import shown because the ESM entry may have no default export; use named imports for what it exports.

CommonJS:

```js
const terser = require("terser");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (205 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 5.21.0 – 5.51.2 | Dual (CommonJS + ESM) | Oct 3, 2023 |

## Frequently asked

**Is terser ESM-only?**

terser@5.51.2 ships CommonJS and ESM builds. terser publishes both a CommonJS entry and a native ESM entry (ESM added in 5.0.0). require("terser") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=10. import "terser" works alongside it.

**Can I require terser?**

Yes. terser ships a CommonJS entry alongside the native ESM entry. require("terser") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=10.

**Does terser work in Bun?**

Yes. import "terser" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does terser ship TypeScript types?**

Yes. terser bundles its own type declarations; no @types package is needed.

## Links

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

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