Online Audio Utilities
This category holds the everyday helpers that are neither tests nor generators. A metronome for practice, a tuner that listens through the microphone, a recorder that keeps a take on your own machine, and a set of conversions that saves you a search. Each one is a single page with no account and no install.
Everything runs in your browser. No audio is ever uploaded.
Tools in this category
What people use these for
The common jobs: practising a passage at a tempo you can raise a few BPM at a time, tuning a guitar that has been in its case since last winter, checking whether a room sounds usable before you record in it, capturing a voice memo without installing anything, and working out the delay time in milliseconds that matches the tempo of the track you are mixing.
How to choose
The metronome and the tuner are the pair most players open together. The metronome runs from 20 to 300 BPM, handles compound time signatures, subdivides the beat into eighths, triplets or sixteenths, and can drop out for a bar so you find out whether you are really keeping time. The tuner has presets for guitar, bass, ukulele and violin, a movable A4 between 415 and 466 Hz, and a cents readout.
The voice recorder is for the moments when you want to hear yourself back: a take, a room, a rehearsal. It records from any input device, shows the waveform while it runs, and hands you a file that never left the machine. The audio calculators cover the conversions that come up mid session, note names to hertz, tempo to delay times in milliseconds, and gain factors to decibels, worked out as you type.
Before you trust the result
Timing and pitch both depend on the browser. The metronome schedules its clicks ahead of time on the audio clock rather than on a JavaScript timer, so it stays steady, but a heavily loaded machine can still stutter. The tuner needs a reasonably clean signal: play one note at a time, get close to the microphone, and keep other sound sources out of the room.