Song key and BPM finder
Drop a file to analyse it. A typical song takes a second or two.
Find the key and BPM of any song. Drop in an MP3 or WAV and this song key finder estimates the key, its Camelot code for harmonic mixing, and the tempo. It runs in your browser, so your file is never uploaded.
How the key and BPM are detected
- Key: the song is broken into short slices and each slice's energy is folded into the 12 pitch classes (C, C♯, D and so on). The overall balance is compared with the Krumhansl-Kessler profiles, which describe how strongly each note belongs in every major and minor key. The closest of the 24 keys wins.
- Tempo: the tool tracks where new sounds start (drum hits, chord changes, plucks) and finds the beat period that lines up with them best.
How accurate is it?
Very good on songs with a steady beat and a clear key; less sure on music that changes key, uses lots of borrowed chords, or has no drums. The usual mix-ups are worth knowing:
- Relative keys: C major and A minor share the same notes, so they are easy to confuse. Both share Camelot number 8, so for mixing it hardly matters.
- Half and double time: a drum and bass track at 174 BPM can read as 87, and a slow hip hop beat as double. The tool shows both; pick the one that feels right, or tap along.
- Your ear decides. Play the key's chord over the song. If it sounds at home, you have the key.
The Camelot wheel
DJs use Camelot codes to mix in key. Tracks with the same code, a number one up or down, or the same number with the other letter (its relative major or minor) blend without clashing.
| Code | Minor key | Code | Major key |
|---|---|---|---|
| 1A | A♭ minor | 1B | B major |
| 2A | E♭ minor | 2B | F♯ major |
| 3A | B♭ minor | 3B | D♭ major |
| 4A | F minor | 4B | A♭ major |
| 5A | C minor | 5B | E♭ major |
| 6A | G minor | 6B | B♭ major |
| 7A | D minor | 7B | F major |
| 8A | A minor | 8B | C major |
| 9A | E minor | 9B | G major |
| 10A | B minor | 10B | D major |
| 11A | F♯ minor | 11B | A major |
| 12A | D♭ minor | 12B | E major |
Cafecito keeps a circle of fifths on every track.
A free plugin for your DAW with a chromatic tuner, an interactive circle of fifths, a Pomodoro timer, notes and to-dos, saved with the session.
Get Cafecito, free →Quick answers
How do I find the key of a song?
Drop the audio file into the key finder above. It estimates the key from the balance of notes across the whole song and shows the Camelot code too. Then play the key's chord over the song to confirm it by ear.
How do I find the BPM of a song?
Drop the file in and the tool estimates the tempo from where the beats land. If the number feels half or double what you hear, use the alternative it shows, or tap along with the Tap button.
What is a Camelot key?
Camelot is a DJ notation that numbers the 24 keys around a wheel, 1 to 12 with A for minor and B for major. Tracks with the same code, a neighbouring number, or the same number with the other letter mix together without clashing.
Why does it say A minor when the song is in C major?
C major and A minor use the same seven notes, so they are hard to tell apart from notes alone. Both are Camelot 8 (8B and 8A). Listen for which chord feels like home.
Is my song uploaded?
No. The file is opened and analysed by your browser on your device. Nothing is sent to a server.
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