var arr = Array(10_000).fill(0)
arr.reduce((acc, x) => [...acc, x, x], [])
arr.flatMap(x => [x, x])
FAQ: FAQ
Source code: GitHub/MeasureThat.net
Report issues: MeasureThat.net/Issues
Based on: Benchmark.js
Facebook page: https://www.facebook.com/MeasureThat.Net
Python benchmarks support: Pyodide