01
DJs and mixers
Camelot codes and compatible keys for harmonic mixing, plus half- and double-time readings for beatmatching across genres.
Analyze a track
Drop in one file or a whole folder. Key, scale, tempo and Camelot code come back in a few seconds — the audio never leaves your device.
Analysis runs in your browser. Nothing is uploaded, and no account is needed.
Keep working with this track
BPM & Key Finder
Find the key, scale and BPM of any song in seconds. Drop in a file and this free BPM finder and key detector analyses it right in your browser — nothing is uploaded.
How it works
How to find the BPM and key of a song
1Step 1
Drop in your audio
Pick one track or select a whole batch. The tempo finder reads MP3, WAV, M4A, FLAC, OGG and AAC — and the file stays on your device, because the analysis engine runs inside the page.
2Step 2
Let it read the track
The BPM detector measures the beat grid twice and compares the two readings, while the key detector estimates the tonic and scale from the harmonic content. A few seconds per song.
3Step 3
Take the numbers with you
Copy the tempo and key straight into your DAW or crate notes, read the Camelot code for harmonic mixing, or jump to the key changer to move the track somewhere else.
What you get
Everything a Key and BPM Finder Should Tell You
Not just a number — the reading, how much to trust it, and what to do with it next.
Accurate BPM detection, with a confidence you can see
The BPM analyzer measures the first and second half of the track separately and reports how closely they agreed. When a song shifts tempo or the transients are soft, you find out instead of copying a wrong number into your session.
A song key finder that gives key, scale and strength
Tonic and mode — C major, F# minor — plus how strongly the harmonic profile supports that reading. Built on the same Essentia analysis library the biggest sites in this category use, running locally instead of on a server.
A key detector with Camelot codes and compatible keys
Every result carries its Camelot code from 1A to 12B and the three keys that mix harmonically against it. That is the difference between knowing the key and being able to use it.
A batch key and BPM finder for a whole folder
Drop in as many files as you like and read the results as one table. No queue, no account, no cap on how many — each file just has to be 50 MB or smaller, because your own browser has to hold it in memory.
Who it's for
Made for People Who Do Something With the Number
Tempo and key are only worth reading if the next step depends on them.
02
Producers
Get a sample's key and tempo before it goes into the session, so it lands in tune with everything already on the timeline.
03
Mashup artists
Find out immediately whether two tracks can sit together, and how many semitones one of them has to move.
04
Music students
Use real records to practise hearing tonic, mode and tempo — then check yourself against the analysis.
FAQ
BPM and key finder questions
Drop the audio file into the analyzer above. It reads the beat grid out of the waveform and reports the tempo in beats per minute, along with the half-time and double-time readings. If you do not have the file — the song is on the radio, or in a room — tap the tempo instead.
Two ways, depending on what you have. With the audio file, an automatic BPM finder like this one is faster and more precise than counting. Without it, tap along to the beat and let a tap tempo tool average your taps.
Drop it in and the key detector reads the tonic and the mode — for example A minor or E♭ major — from the track's harmonic content, and shows how strongly the audio supports that reading.
By ear, you would find the note the song resolves to and decide whether the third above it is major or minor. This song key finder does the same thing statistically: it builds a pitch profile across the track and matches it against all 24 keys.
A numbering system for harmonic mixing. Each key gets a number from 1 to 12 and a letter — A for minor, B for major — so 8A is A minor and 8B is C major. Any two tracks whose codes share a number, or sit one number apart on the same letter, will mix in tune.
Because tempo can be counted at more than one level, and both readings are musically correct. Drum and bass at 174 BPM is often counted at 87; a slow hip-hop beat written at 70 gets counted at 140. Every result here shows both, so you can pick the one your session uses.
Key and tempo detection are estimates, not measurements — no tool in this category is exact. This one reads a window from the middle of the track, cross-checks the tempo across two halves, and shows you the agreement so a shaky result is visible rather than hidden behind a confident-looking number.
No. The analysis engine is WebAssembly running inside this page, so the audio is decoded and measured on your own machine. Nothing is sent to a server, which is also why there is no queue and no cap on how many files you analyse. The one ceiling is 50 MB per file, because your browser has to hold it in memory.
It is free and there is no account. Analyse as many tracks as you like — since the work happens in your browser, it costs us nothing to run.
Know your track's key and BPM
A free BPM and key finder with Camelot codes and compatible keys, running entirely in your browser.