BPM Finder

Drop in a song — MP3, WAV, AAC, FLAC or anything else your browser can play — or let it listen through your microphone, and it works out the tempo. Everything happens in your browser: the audio never leaves your device. Prefer to tap along? Use the tap tempo counter.

How it works

The finder listens for onsets — the moments a new sound starts, like a kick drum or a strummed chord — mostly in the low end, where the kick, snare and bass carry the beat. Then it looks for the gap those onsets repeat at most strongly, and that gap is the beat. A long file is read from a 90-second stretch a third of the way in, where the groove has usually settled.

Why two numbers?

Tempo has a built-in half-or-double ambiguity: a song at 87 BPM and the same song felt at 174 share a pulse, one just counts every other beat. So the finder gives its best guess first and the other reading next to it. Pick the one that matches how you count the song. DJ software and streaming services often disagree in exactly this way.

Getting a good reading

Use music with a clear beat: drums, or a strong bass or rhythm guitar. Rubato classical music, ambient pieces and songs that change tempo give a rough average at best. With the microphone, play the music reasonably loud near the phone or laptop and keep talking to a minimum; the reading firms up after 10–15 seconds.

Want to check it by ear? Tap along on the BPM counter, or read how to find a song’s BPM by hand.