Maker here. I built these because I kept opening five tabs of janky online calculators to answer one listener email. Everything runs client-side via Web Audio API: your audio files never leave the browser, there is no account, there is no upsell. The set covers what professional audio software charges hundreds for: amp power math (mW, RMS volts, peak voltage swing), room mode mapping up to 300 Hz, level-matched ABX double-blind testing with a result certificate, FFT spectrogram for catching upsampled "hi-res" fakes, Golden Ear frequency training, cable gauge math, and WHO safe-listening duration from headphone sensitivity. Built to answer the real questions: will this 100 W amp drive my HE-R10? Is this 192 kHz FLAC actually hi-res or upsampled? Where do I sit in a 4x5 m room to avoid the worst nulls? If you want a tool added that would be useful, drop it in the comments and I will build it.

The Audio Stuff Tools

12 free in-browser audio tools - no signup, no upload

12 free in-browser audio tools - no signup, no upload