moon-cycle/.github/wiki/benchmarks/index.md

Performance Benchmarks

Mapping performance

Measured on Node 22, Apple M2. Input: 1,000 random dates in the range 2000-2030.

Operation	Time
cycleMonth(date)	~0.8 µs/call
cycleYear(date)	~1.1 µs/call
cdnUrl(filename, set, size, quality)	~0.2 µs/call
imageFolder(set, size, quality)	~0.1 µs/call

All mapping functions are pure arithmetic with no I/O. The result is a string — no images are loaded.

Network performance (CDN)

When using cdnUrl(), the returned URL points to jsDelivr, which serves from a global CDN with ~25ms p50 latency to most regions. Image files are typically 5-25 KB per WebP depending on the phase and quality setting.

Image size	Approx. file size
64px, quality 75	~2-5 KB
128px, quality 75	~5-10 KB
256px, quality 75	~10-20 KB
512px, quality 85	~25-60 KB

For best performance in high-traffic applications, self-host the image folders and serve them from your own CDN. See Self-hosting.

Reproducing the benchmarks

import { cycleMonth, cdnUrl } from 'moon-cycle';

const dates = Array.from({ length: 1000 }, (_, i) => {
  const d = new Date(2000, 0, 1);
  d.setDate(d.getDate() + i * 10);
  return d;
});

const start = performance.now();
for (const date of dates) {
  cycleMonth(date);
}
const elapsed = performance.now() - start;
console.log(`${(elapsed / dates.length * 1000).toFixed(1)} µs/call`);

Run with node --version >= 20.