# @csstools/selector-specificity

> Determine selector specificity with postcss-selector-parser

Latest version **6.0.0** (published 2026-01-14) · MIT-0 license · 0 weekly downloads

## Install

```sh
npm install @csstools/selector-specificity
pnpm add @csstools/selector-specificity
yarn add @csstools/selector-specificity
bun add @csstools/selector-specificity
```

## Health

**Score 55/100 (C)** — status: stable.

Positive: esm support; no vulnerabilities; high maintenance score.

Warnings: low downloads; no types.

## Facts

| | |
|---|---|
| Version | 6.0.0 |
| Published | 2026-01-14 |
| First published | 2022-04-26 |
| Weekly downloads | 0 |
| License | MIT-0 |
| TypeScript types | none |
| Module format | ESM |
| Node | >=20.19.0 |
| Dependencies | 0 |
| Unpacked size | 8.8 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 1053 |
| Maintainers | jonathantneal, alaguna, romainmenke |
| Keywords | css, postcss-selector-parser, specificity |

## Links

- npm: https://www.npmjs.com/package/@csstools/selector-specificity
- Repository: https://github.com/csstools/postcss-plugins
- Homepage: https://github.com/csstools/postcss-plugins/tree/main/packages/selector-specificity#readme
- Issues: https://github.com/csstools/postcss-plugins/issues
- Funding: https://github.com/sponsors/csstools
- npm.io page: https://npm.io/package/@csstools/selector-specificity

## 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
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- [mat4-interpolate](https://npm.io/package/mat4-interpolate.md) — 23.3K weekly downloads

## Recent versions

- 6.0.0 (latest) — 2026-01-14
- 5.0.0 — 2024-10-23
- 4.0.0 — 2024-08-03
- 3.1.1 — 2024-05-13
- 3.1.0 — 2024-05-11
- 3.0.3 — 2024-03-31
- 3.0.2 — 2024-02-19
- 3.0.1 — 2023-12-15
- 3.0.0 — 2023-07-03
- 2.2.0 — 2023-03-21
- 2.1.1 — 2023-01-28
- 2.1.0 — 2023-01-19
- 2.0.2 — 2022-07-08
- 2.0.1 — 2022-06-10
- 2.0.0 — 2022-06-04
- … 1 more at https://npm.io/package/@csstools/selector-specificity/versions

## README

# Selector Specificity [<img src="https://postcss.github.io/postcss/logo.svg" alt="for PostCSS" width="90" height="90" align="right">][postcss]

[<img alt="npm version" src="https://img.shields.io/npm/v/@csstools/selector-specificity.svg" height="20">][npm-url]
[<img alt="Build Status" src="https://github.com/csstools/postcss-plugins/actions/workflows/test.yml/badge.svg?branch=main" height="20">][cli-url]
[<img alt="Discord" src="https://shields.io/badge/Discord-5865F2?logo=discord&logoColor=white">][discord]

## Usage

Add [Selector Specificity] to your project:

```bash
npm install @csstools/selector-specificity --save-dev
```

```js
import parser from 'postcss-selector-parser';
import { selectorSpecificity } from '@csstools/selector-specificity';

const selectorAST = parser().astSync('#foo:has(> .foo)');
const specificity = selectorSpecificity(selectorAST);

console.log(specificity.a); // 1
console.log(specificity.b); // 1
console.log(specificity.c); // 0
```

_`selectorSpecificity` takes a single selector, not a list of selectors (not : `a, b, c`).
To compare or otherwise manipulate lists of selectors you need to call `selectorSpecificity` on each part._

### Comparing

The package exports a utility function to compare two specificities.

```js
import { selectorSpecificity, compare } from '@csstools/selector-specificity';

const s1 = selectorSpecificity(ast1);
const s2 = selectorSpecificity(ast2);
compare(s1, s2); // -1 | 0 | 1
```

- if `s1 < s2` then `compare(s1, s2)` returns a negative number (`< 0`)
- if `s1 > s2` then `compare(s1, s2)` returns a positive number (`> 0`)
- if `s1 === s2` then `compare(s1, s2)` returns zero (`=== 0`)

## Prior Art

- [keeganstreet/specificity](https://github.com/keeganstreet/specificity)
- [bramus/specificity](https://github.com/bramus/specificity)

For CSSTools we always use `postcss-selector-parser` and want to calculate specificity from this AST.

[cli-url]: https://github.com/csstools/postcss-plugins/actions/workflows/test.yml?query=workflow/test
[discord]: https://discord.gg/bUadyRwkJS
[npm-url]: https://www.npmjs.com/package/@csstools/selector-specificity
[postcss]: https://github.com/postcss/postcss

[Selector Specificity]: https://github.com/csstools/postcss-plugins/tree/main/packages/selector-specificity

---
_Source: https://npm.io/package/@csstools/selector-specificity · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._