PostCSS Benchmarks

Various benchmarks to have feedback about PostCSS perfomance.

---

  CSS Benchmark is built by Evil Martians, an American design and engineering consultancy for developer tools, AI, and cybersecurity startups.

---

All results below was run on Node 20.3.1, Github Actions:

Preprocessors

Compare CSS processors for parsings, nested rules, mixins, variables and math:

PostCSS sync:   70 ms  (1.0 times faster)
PostCSS:        72 ms
LibSass sync:   118 ms (1.6 times slower)
LibSass:        123 ms (1.7 times slower)
Less:           139 ms (1.9 times slower)
Dart Sass sync: 219 ms (3.0 times slower)
Dart Sass:      397 ms (5.5 times slower)

To get results on your environment:

pnpm install
pnpm test preprocessors

Parsers

Compare CSS parsers written on JS:

Stylis:       15 ms  (1.8 times faster)
CSSOM:        24 ms  (1.2 times faster)
PostCSS:      28 ms
CSSTree:      37 ms  (1.3 times slower)
Mensch:       37 ms  (1.3 times slower)
Rework:       49 ms  (1.8 times slower)
Stylecow:     73 ms  (2.6 times slower)
PostCSS Full: 95 ms  (3.4 times slower)
ParserLib:    153 ms (5.5 times slower)
Gonzales:     177 ms (6.4 times slower)

To get results on your environment:

pnpm install
pnpm test parsers

Prefixers

Compare vendor prefixes tools:

Lightning CSS: 12 ms   (7.7 times faster)
Stylis:        18 ms   (5.3 times faster)
Autoprefixer:  96 ms
Stylecow:      1009 ms (10.5 times slower)

To get results on your environment:

pnpm install
pnpm test prefixers