# Is @csstools/color-helpers ESM-only? Can you require() it?

> @csstools/color-helpers@6.1.1 is ESM-only. ESM-only since 6.0.0 — last CommonJS version is 5.1.0.

Color helpers to ease transformation between formats, gamut, etc

Last verified Sep 9, 2026 against @csstools/color-helpers@6.1.1.

@csstools/color-helpers dropped its CommonJS build in 6.0.0 (January 2026). The last version with a plain require()-able CommonJS entry is 5.1.0, published Aug 22, 2025; it declares support for Node.js >=18.

On Node.js 20.19+, 22.12+ and newer, require("@csstools/color-helpers") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26. Node.js 18 has no require(esm), and @csstools/color-helpers@6.1.1 declares Node.js >=20.19.0, so 18 is outside its supported range anyway.

@csstools/color-helpers@6.1.1 declares engines ">=20.19.0", so Node.js 18 is outside its supported range regardless of module format.

## What to do

1. On Node.js 20.19+, 22.12+ and newer, require("@csstools/color-helpers") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26.
2. From a CommonJS file, use a dynamic import inside an async function: const colorHelpers = await import("@csstools/color-helpers"). That works on every Node.js version the package supports (>=20.19.0).
3. If you need a synchronous require() or run Node.js 18: npm install @csstools/color-helpers@5.1.0, the last CommonJS release (published Aug 22, 2025); it declares Node.js >=18.
4. @csstools/color-helpers@6.1.1 declares engines ">=20.19.0", so Node.js 18 is unsupported regardless: upgrade Node.js or pin an older release.
5. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 6.1.1 (Aug 15, 2026)
- Module format: ESM-only
- Last CommonJS version: 5.1.0
- ESM-only since: 6.0.0 (Jan 14, 2026)
- TypeScript types: bundled
- Node engines: >=20.19.0
- Weekly downloads: 38.8M
- License: MIT-0

## Runtime test results for @csstools/color-helpers@6.1.1

Installed and executed on Sep 9, 2026 with require("@csstools/color-helpers") from a CommonJS file and import "@csstools/color-helpers" from an ES module.

| Runtime | require("@csstools/color-helpers") | import "@csstools/color-helpers" |
|---|---|---|
| Node.js 18 | fails (ERR_REQUIRE_ESM) | 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 @csstools/color-helpers

ES modules:

```js
import * as colorHelpers from "@csstools/color-helpers";
```

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

CommonJS:

```js
// Node.js 20.19+, 22.12+ and newer (verified):
const colorHelpers = require("@csstools/color-helpers");

// Any Node.js version the package supports (>=20.19.0), from an async function:
async function main() {
  const colorHelpers = await import("@csstools/color-helpers");
}

// Or pin the last CommonJS release (declares Node.js >=18):
// npm install @csstools/color-helpers@5.1.0
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (19 versions; the newest 19 shown).

| Versions | Format | First published |
|---|---|---|
| 6.0.0 – 6.1.1 | ESM-only | Jan 14, 2026 |
| 1.0.0 – 5.1.0 | Dual (CommonJS + ESM) | Feb 2, 2023 |

## Frequently asked

**Is @csstools/color-helpers ESM-only?**

@csstools/color-helpers@6.1.1 is ESM-only. @csstools/color-helpers dropped its CommonJS build in 6.0.0 (January 2026). The last version with a plain require()-able CommonJS entry is 5.1.0, published Aug 22, 2025; it declares support for Node.js >=18.

**Which version of @csstools/color-helpers still supports CommonJS / require()?**

5.1.0 is the last version of @csstools/color-helpers with a CommonJS build; it declares Node.js >=18. Install it with "npm install @csstools/color-helpers@5.1.0". Every version from 6.0.0 on is ESM-only.

**How do I use @csstools/color-helpers from a CommonJS file?**

From a CommonJS file, use a dynamic import inside an async function: const colorHelpers = await import("@csstools/color-helpers"). That works on every Node.js version the package supports (>=20.19.0). On Node.js 20.19+, 22.12+ and newer, require("@csstools/color-helpers") works with the latest version: Node.js loads synchronous ES modules through require(). Verified on Node.js 20, 22, 24 and 26. Alternatively pin @csstools/color-helpers@5.1.0 (declares Node.js >=18).

**Does @csstools/color-helpers work in Bun?**

Yes. import "@csstools/color-helpers" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does @csstools/color-helpers ship TypeScript types?**

Yes. @csstools/color-helpers bundles its own type declarations; no @types package is needed.

## Links

- [@csstools/color-helpers on npm](https://www.npmjs.com/package/@csstools/color-helpers)
- [Source repository](https://github.com/csstools/postcss-plugins)
- [HTML version](https://canirequire.com/package/@csstools/color-helpers/)
- [JSON version](https://canirequire.com/package/@csstools/color-helpers.json)

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