Compares the speed and package size of various ECMAScript parsers and code generators.
The new contender meriyah runs twice as fast as the old bard esprima. Babel produces an AST, which is not compatible with the other parsers.
Generating code with astring is faster than with escodegen.
git clone https://github.com/prantlf/ecmascript-parser-benchmark.git
cd ecmascript-parser-benchmark
pnpm i
npm start
$ node perf/script && node perf/module && \
node perf/script --locations && node perf/module --locations
Parsing jquery.js as a script by...
esprima x 91.91 ops/sec ±0.85% (78 runs sampled)
acorn x 91.55 ops/sec ±0.49% (79 runs sampled)
babel x 46.68 ops/sec ±2.53% (62 runs sampled)
hermes x 26.12 ops/sec ±4.30% (47 runs sampled)
meriyah x 151 ops/sec ±2.41% (71 runs sampled)
kataw x 87.17 ops/sec ±3.11% (65 runs sampled)
seafox x 109 ops/sec ±1.81% (80 runs sampled)
cherow x 142 ops/sec ±1.78% (78 runs sampled)
escaya x 93.83 ops/sec ±2.06% (69 runs sampled)
tenko x 62.02 ops/sec ±7.86% (67 runs sampled)
tree-sitter x 29.87 ops/sec ±1.67% (46 runs sampled)
Parsing collection-view.js as a module by...
esprima x 1,581 ops/sec ±0.73% (92 runs sampled)
acorn x 1,502 ops/sec ±0.44% (93 runs sampled)
babel x 1,278 ops/sec ±1.02% (91 runs sampled)
hermes x 532 ops/sec ±0.93% (92 runs sampled)
meriyah x 3,107 ops/sec ±1.16% (94 runs sampled)
kataw x 2,491 ops/sec ±0.79% (96 runs sampled)
seafox x 2,613 ops/sec ±0.58% (90 runs sampled)
cherow x 2,877 ops/sec ±1.42% (91 runs sampled)
escaya x 2,760 ops/sec ±0.82% (94 runs sampled)
tenko x 1,183 ops/sec ±0.90% (93 runs sampled)
tree-sitter x 479 ops/sec ±0.71% (84 runs sampled)
Parsing jquery.js as a script with locations by...
esprima x 79.59 ops/sec ±0.46% (69 runs sampled)
acorn x 53.86 ops/sec ±2.22% (59 runs sampled)
babel x 40.50 ops/sec ±6.18% (55 runs sampled)
hermes x 26.04 ops/sec ±4.52% (48 runs sampled)
meriyah x 108 ops/sec ±1.07% (71 runs sampled)
kataw x 89.44 ops/sec ±3.12% (67 runs sampled)
seafox x 86.19 ops/sec ±3.31% (69 runs sampled)
cherow x 82.27 ops/sec ±2.72% (64 runs sampled)
escaya x 83.81 ops/sec ±2.18% (72 runs sampled)
tenko x 51.95 ops/sec ±7.58% (58 runs sampled)
tree-sitter x 30.92 ops/sec ±1.55% (49 runs sampled)
Parsing collection-view.js as a module with locations by...
esprima x 1,424 ops/sec ±0.63% (94 runs sampled)
acorn x 1,349 ops/sec ±0.66% (93 runs sampled)
babel x 1,213 ops/sec ±1.01% (90 runs sampled)
hermes x 537 ops/sec ±0.85% (93 runs sampled)
meriyah x 2,514 ops/sec ±0.50% (92 runs sampled)
kataw x 2,506 ops/sec ±0.68% (93 runs sampled)
seafox x 2,398 ops/sec ±0.67% (91 runs sampled)
cherow x 2,595 ops/sec ±0.86% (94 runs sampled)
escaya x 2,549 ops/sec ±0.66% (93 runs sampled)
tenko x 1,157 ops/sec ±0.77% (93 runs sampled)
tree-sitter x 469 ops/sec ±1.06% (81 runs sampled)
The hermes parser always creates an AST with source code locations. They cannot be disabled to gain more performance.
The tree-sitter parser always creates an AST with source code locations. They cannot be disabled to gain more performance. It makes no difference between a script and a module either.
$ node perf/generator && node perf/generator --source-map
Generating code for an AST from jquery.js by...
escodegen x 91.99 ops/sec ±1.57% (73 runs sampled)
astring x 362 ops/sec ±1.21% (83 runs sampled)
babel x 28.71 ops/sec ±4.65% (52 runs sampled)
Generating code with source maps for an AST from jquery.js by...
escodegen x 4.47 ops/sec ±6.08% (16 runs sampled)
astring x 98.70 ops/sec ±1.40% (72 runs sampled)
babel x 16.80 ops/sec ±6.85% (33 runs sampled)
$ package-size esprima acorn @babel/parser hermes meriyah seafox kataw \
cherow @azariasb/escaya tenko tree-sitter tree-sitter-javascript
package size minified gzipped
[email protected] 278.47 KB 132.14 KB 28.59 KB
[email protected] 206.72 KB 107.29 KB 30.81 KB
@babel/[email protected] 469.98 KB 271 KB 69.84 KB
[email protected] 308.87 KB 53.94 KB 17.98 KB
[email protected] 128.94 KB 127.33 KB 40.25 KB
[email protected] 95 KB 93.41 KB 25.57 KB
[email protected] 297.65 KB 291.29 KB 59.47 KB
[email protected] 300.63 KB 89.85 KB 25.12 KB
@azariasb/[email protected] 98.24 KB 96.53 KB 25.97 KB
[email protected] 371.71 KB 142.41 KB 39.75 KB
[email protected] 51.28 KB 22.81 KB 6.8 KB
[email protected] 37.99 KB 29.81 KB 2.68 KB
$ package-size escodegen astring
package size minified gzipped
[email protected] 278.79 KB 96.82 KB 25.41 KB
[email protected] 35.61 KB 15.4 KB 4.26 KB
Estimating the size of @babel/generator failed.
In lieu of a formal styleguide, take care to maintain the existing coding style. Lint and test your code.
Copyright (c) 2022 Ferdinand Prantl
Licensed under the MIT license.