# postcss-merge-rules

> Merge CSS rules with PostCSS.

Latest version **9.0.4** (published 2026-09-17) · MIT license · 0 weekly downloads

## Install

```sh
npm install postcss-merge-rules
pnpm add postcss-merge-rules
yarn add postcss-merge-rules
bun add postcss-merge-rules
```

## Health

**Score 75/100 (B)** — status: active.

Positive: has types; esm support; no vulnerabilities; has provenance; recently updated; high maintenance score; high quality score.

Warnings: low downloads.

## Facts

| | |
|---|---|
| Version | 9.0.4 |
| Published | 2026-09-17 |
| First published | 2015-03-27 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Node | ^22.22.3 \|\| ^24.15.0 \|\| >=26.0 |
| Dependencies | 4 |
| Unpacked size | 114.8 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 4975 |
| Author | Ben Briggs |
| Maintainers | beneb, trysound, ludovicofischer, ai, chriseppstein, andyjansson, evilebottnawi, cssnano-bot |
| Keywords | css, optimise, postcss, postcss-plugin |

## Links

- npm: https://www.npmjs.com/package/postcss-merge-rules
- Repository: https://github.com/cssnano/cssnano
- Issues: https://github.com/cssnano/cssnano/issues
- npm.io page: https://npm.io/package/postcss-merge-rules

## Dependencies (4)

- [caniuse-api](https://npm.io/package/caniuse-api.md) ^4.0.0
- [browserslist](https://npm.io/package/browserslist.md) ^4.29.0
- [cssnano-utils](https://npm.io/package/cssnano-utils.md) ^7.0.3
- [postcss-selector-parser](https://npm.io/package/postcss-selector-parser.md) ^7.1.6

## Alternatives

- [style-dictionary](https://npm.io/package/style-dictionary.md) — 2.0M weekly downloads
- [postcss-merge-idents](https://npm.io/package/postcss-merge-idents.md) — 1.7M weekly downloads
- [@fontsource/noto-sans](https://npm.io/package/@fontsource/noto-sans.md) — 93.0K weekly downloads
- [uglifycss](https://npm.io/package/uglifycss.md) — 71.6K weekly downloads
- [mat4-interpolate](https://npm.io/package/mat4-interpolate.md) — 23.3K weekly downloads

## Recent versions

- 9.0.4 (latest) — 2026-09-17
- 5.0.0-rc.2 (next) — 2021-03-15
- 4.0.0-nightly.2020.2.6 (nightly) — 2021-02-06
- 9.0.3 — 2026-09-05
- 9.0.2 — 2026-09-01
- 9.0.1 — 2026-08-28
- 9.0.0 — 2026-08-27
- 8.0.5 — 2026-08-20
- 8.0.4 — 2026-08-16
- 8.0.3 — 2026-08-09
- 8.0.2 — 2026-08-04
- 8.0.1 — 2026-06-11
- 8.0.0 — 2026-05-06
- 7.0.11 — 2026-05-02
- 7.0.10 — 2026-04-20
- … 81 more at https://npm.io/package/postcss-merge-rules/versions

## README

# [postcss][postcss]-merge-rules

> Merge CSS rules with PostCSS.

## Install

With [npm](https://npmjs.org/package/postcss-merge-rules) do:

```
npm install postcss-merge-rules --save
```

## Examples

This module will attempt to merge *adjacent* CSS rules:

### By declarations

#### Input

```css
a {
    color: blue;
    font-weight: bold
}

p {
    color: blue;
    font-weight: bold
}
```

#### Output

```css
a,p {
    color: blue;
    font-weight: bold
}
```

### By selectors

#### Input

```css
a {
    color: blue
}

a {
    font-weight: bold
}
```

#### Output

```css
a {
    color: blue;
    font-weight: bold
}
```

### By partial declarations

#### Input

```css
a {
    font-weight: bold
}

p {
    color: blue;
    font-weight: bold
}
```

#### Output

```css
a,p {
    font-weight: bold
}

p {
    color: blue
}
```

## Usage

See the [PostCSS documentation](https://github.com/postcss/postcss#usage) for
examples for your environment.

## Contributors

See [CONTRIBUTORS.md](https://github.com/cssnano/cssnano/blob/main/CONTRIBUTORS.md).

## License

MIT © [Ben Briggs](https://beneb.info)

[postcss]: https://github.com/postcss/postcss

---
_Source: https://npm.io/package/postcss-merge-rules · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._