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

> less-loader@13.0.0 ships CommonJS and ESM builds. Dual package — require() works on every Node.js version we test; import works too.

A Less loader for webpack. Compiles Less to CSS.

Last verified Sep 9, 2026 against less-loader@13.0.0.

less-loader publishes both a CommonJS entry and a native ESM entry (ESM added in 13.0.0). require("less-loader") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 22.11.0. import "less-loader" works alongside it.

## What to do

1. Nothing to change. require("less-loader") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 22.11.0. import * as lessLoader from "less-loader" works alongside it; use named imports for what the ESM entry exports.
2. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 13.0.0 (May 20, 2026)
- Module format: Dual (CommonJS + ESM)
- Last CommonJS version: 13.0.0
- Native ESM since: 13.0.0
- TypeScript types: bundled
- Node engines: >= 22.11.0
- Weekly downloads: 6.2M
- License: MIT

## Runtime test results for less-loader@13.0.0

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

| Runtime | require("less-loader") | import "less-loader" |
|---|---|---|
| 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 less-loader

ES modules:

```js
import * as lessLoader from "less-loader";
```

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

CommonJS:

```js
const lessLoader = require("less-loader");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (73 versions; the newest 60 shown).

| Versions | Format | First published |
|---|---|---|
| 13.0.0 | Dual (CommonJS + ESM) | May 20, 2026 |
| 0.7.1 – 12.3.3 | CommonJS | Jan 28, 2014 |

## Frequently asked

**Is less-loader ESM-only?**

less-loader@13.0.0 ships CommonJS and ESM builds. less-loader publishes both a CommonJS entry and a native ESM entry (ESM added in 13.0.0). require("less-loader") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 22.11.0. import "less-loader" works alongside it.

**Can I require less-loader?**

Yes. less-loader ships a CommonJS entry alongside the native ESM entry. require("less-loader") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 22.11.0.

**Does less-loader work in Bun?**

Yes. import "less-loader" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does less-loader ship TypeScript types?**

Yes. less-loader bundles its own type declarations; no @types package is needed.

## Links

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

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