This article The State of Benchmarking in Node.js is quite useful to follow.

It also points to a library like mitata which is used by Bun and Deno.

A simple example

First, set up a new project:

$ mkdir demo-mitata-benchmarking
$ cd demo-mitata-benchmarking
$ npm init -y
$ mkdir src
$ touch src/example.mjs
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As for the code within src/example.mjs

import { run, bench, group, baseline } from 'mitata'

function add(x, y) {
    return x + y;
}

function add2(x) {
    return add(x, 2);
}

group('add', () => {
    baseline('add', () => add(1, 2));
    bench('add2', () => add2(1));
})

await run();
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Running the results:

$ node src/example.mjs
cpu: Apple M2 Pro
runtime: node v20.10.0 (arm64-darwin)

benchmark      time (avg)             (min … max)       p75       p99      p999
------------------------------------------------- -----------------------------
• add
------------------------------------------------- -----------------------------
add           461 ps/iter     (386 ps … 57.43 ns)    448 ps    570 ps   4.23 ns
add2         3.84 ns/iter    (3.64 ns … 40.18 ns)   3.84 ns   7.55 ns   9.99 ns

summary for add
  add
   8.32x faster than add2
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