BPM and key finder
Find the tempo and key of a song in a couple of seconds. Drop in an audio file and get its BPM, key, Camelot code and relative key. No sign-up, and the file never leaves your device.
How it works
The tempo comes from the rhythm: the tool finds where notes and drums start, then looks for the beat length that repeats most strongly across several bars. The key comes from the harmony: it measures how much of each of the 12 notes the song uses and compares that profile with every major and minor key.
Reading the results
- Half or double time: many songs can be counted either way, so the tool also shows half and double the tempo. Pick the one that matches how you'd clap along.
- Relative keys: A minor and C major use the same notes. If the result feels off, try the relative key it shows.
- Camelot code: DJs use it for harmonic mixing. Codes with the same number, or one step apart, mix smoothly.
- Songs that change tempo or key: the tool reads the middle two minutes of the track and reports the main tempo and key.
Questions
Is my file uploaded?
No. The file is decoded and analysed inside your browser tab. Nothing is sent to our servers.
Which formats work?
Anything your browser can play: MP3, WAV, M4A/AAC, and FLAC or OGG in most browsers. Files up to 100 MB.
How accurate is it?
Tempo is usually exact for songs with a steady beat. Key detection is an estimate: songs that change key, or sit between a key and its relative minor or major, can confuse it. The result shows how sure it is.
Why is the BPM half or double what I expected?
A beat can be counted at different levels. The tool picks the one most songs are counted at, and shows half and double alongside it.
Is it free?
Yes, with no sign-up and no limit, because it runs on your own device.