Free tool · Key and BPM
Key and BPM Finder: what key is this song in?
Drop a song, a beat, a loop or a vocal and we'll tell you its key (major or minor), its BPM and its relative key. Plus the Camelot code and the keys that mix well with it. Free, no account, no usage limits.
🔒 Your audio never leaves your computer: it is analyzed in this browser. We don’t upload it or store it.
Want it inside your DAW, live? The A-Radar Pro shows key, scale and tempo on a track while it plays. €19 incl. taxes.
Or the whole studio: 11 plugins for €9.99/month (over €555 if bought one by one), including the A-Vocal FX to tune your vocal to the key you got here. Incl. taxes.
Try our plugin subscription free for 7 days See the A-Radar Pro
What the key finder tells you
The key and whether it's major or minor (A minor = Am). The Camelot code, for harmonic mixing. The relative key, which uses the same notes. The keys that mix well with yours. A second guess, in case the first one doesn't sound right. And the tuning in cents against A = 440 Hz: if a sample is at 432 Hz or a little flat, you'll see it here before it clashes with your beat.
Why the key matters
Sampling without clashes. If the sample is in F minor and your beat is in E minor, pitch it down a semitone first. Recording vocals. With the key, the pitch corrector knows which notes to pull the voice to. DJ mixing without notes fighting: use the Camelot code. Remixes and covers: transpose the track to a key that suits the singer.
Got the key? Tune the vocal to it
The pitch corrector in the A-Vocal FX has all twelve keys, four scales and two modes: natural, so nobody notices, and hard, for the trap and reggaeton effect. Set it to the key you got here and the voice lands on the right notes. Try it free for 7 days.
Want it inside your DAW, live? The A-Radar Pro (€19 incl. taxes) does the same on a track: key, scale and tempo while it plays, no exporting. And to check how loud your mix is, the A-Parallax is free.
Circle of fifths (and fourths): where your key sits
When you analyze a file, its key lights up here and its neighbours are marked. Major keys are on the outside; inside is each one's relative minor, which uses the same notes.
How to read it. Clockwise, each step goes up a fifth (C → G → D). Counter-clockwise, each step goes up a fourth (C → F → B♭): it's the same circle read backwards, which is why it's also called the circle of fourths. Each step to the right adds a sharp to the key signature; each step to the left adds a flat.
Why it helps when you record or produce. The chords that sound best in your key are the key itself and its two neighbours, plus their relative minors: in C major, that's C, F and G, plus Am, Dm and Em. Neighbouring keys differ by a single note, so they're the natural place to modulate in a bridge or to drop in a sample that won't clash. The further apart on the circle, the more notes differ and the more they clash.
The Camelot wheel below is this same circle, numbered for DJs: 8B is C major, 9B is G major and 8A is A minor.
Camelot wheel: all 24 keys
To mix two songs without clashes, stay on the same number, move one up or down, or swap the letter on the same number.
| Code | Minor key | Code | Major key |
|---|---|---|---|
| 1A | G♯ / A♭ minor | 1B | B major |
| 2A | D♯ / E♭ minor | 2B | F♯ / G♭ major |
| 3A | A♯ / B♭ minor | 3B | C♯ / D♭ major |
| 4A | F minor | 4B | G♯ / A♭ major |
| 5A | C minor | 5B | D♯ / E♭ major |
| 6A | G minor | 6B | A♯ / 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♯ / G♭ minor | 11B | A major |
| 12A | C♯ / D♭ minor | 12B | E major |
We measured it
We don't trust a "99% accurate" claim that doesn't say against what. So we measured it: 220 loops and beats with the key written in the file name and 157 with the tempo, taken from trap, reggaeton and phonk sample libraries. We ran the same files through our detector and through Essentia, the music analysis library from Universitat Pompeu Fabra.
Exact key: 104 out of 220, Essentia 105. Key signature (the key or its relative): 128 out of 220, Essentia 123.
The BPM, or its half or double, on 87 out of 100 loops. Essentia: 83.
Measured on an Apple-silicon Mac. It runs on your computer: no queue, no server.
File-name labels aren't perfect, and the key of a short loop or a pad with no bass is genuinely ambiguous, so no detector gets close to 100% on this kind of material. That's why we also show the second guess, the relative key and the half- and double-time BPM: if the first answer doesn't sound right, it's almost always one of those.
FAQ
How do I find the key of a song?
Drop it into the box above (MP3, WAV, FLAC, M4A, OGG or AAC). In a few seconds you'll see the key, whether it's major or minor, its Camelot code and its relative key. To check by ear, play the note we give you over the chorus: it should sound like "home".
Is my song uploaded anywhere?
No. The file is decoded and analyzed inside your browser with an engine we wrote ourselves. It never leaves your computer and we don't store it: you can check by going offline after the page loads.
Why does it sometimes say A minor and sometimes C major?
They're relative keys: same notes, only the "home" note changes. On a short loop with no bass even a musician might not be able to tell. That's why we show the relative key and a second guess.
What is the Camelot code?
A way of numbering the 24 keys for harmonic mixing: 8A is A minor, 8B is C major. The same number, the next one over (7A, 9A) and the letter swap (8A ↔ 8B) all mix well. Full table below.
Does it work on vocals, samples and loops?
On anything with notes: songs, beats, melodic loops, acapellas and vocals. A drums-only loop has no key, but it does have a BPM.
Is this a Tunebat or Mixed In Key alternative?
For finding the key and BPM of your own file, yes: drop it in and you're done, including music you haven't released yet. No account, no usage limit, nothing to install, and the measurement is published.
What is the circle of fifths?
The 12 major keys arranged in a circle so that each one is a fifth away from the next (C, G, D, A…), with its relative minor alongside. Read backwards it moves in fourths (C, F, B♭…), which is why it's also called the circle of fourths. Neighbouring keys share every note but one, so they're the ones that combine best. On this page, your file's key lights up on it.
Can I analyze several files at once?
Yes: drop as many as you like and they're analyzed one after another, each on its own card with a button to copy "Am · 140 BPM · 8A".