Song key finder
The key of a track, and the number a DJ mixes it by.
Drop files here
or click to choose from your deviceAccepted: MP3, M4A, AAC, WAV, OGG, OGA, OPUS, FLAC, WEBA, MP4, M4V, WEBM, MOV, MKV
Up to 3 files per runUp to 20 MB per file10 runs per dayRemove limits with Pro✓ Works offline
Your files stay on your device
This tool runs entirely in your browser. Nothing is uploaded, nothing is stored, and you can even turn off your internet connection before you start.
How it works
- Add a track — MP3, M4A, WAV, FLAC, or a video, whose sound is read.
- Wait a moment: a minute from the middle of the track is measured note by note.
- Read the key and its Camelot number, with the next closest key under it.
- Mix with tracks whose Camelot number is the same or one step away, or transpose to match.
Frequently asked questions
- How does it work?
- It measures how much of each of the twelve notes is sounding across five octaves, then compares that with the profiles Krumhansl and Kessler measured for major and minor keys. The key whose profile fits best is the answer.
- What is the Camelot number?
- The wheel DJs use: C major is 8B and its relative minor, A minor, is 8A. Tracks with the same number, or one step around the wheel, or the same number in the other letter, generally mix without clashing.
- How accurate is it?
- Good on music with clear harmony. The common mistake is between a key and its relative — A minor and C major share every note, and only emphasis tells them apart — which is why the next closest key is printed too. A track that changes key has no single answer.
- Is my music uploaded?
- No. It is analysed in your browser and nothing leaves your computer.
Related tools
♩ BPM detector The tempo of a track, read from where the sound gets louder. ♯ Change the key of a song Move a song up or down by semitones at the same tempo, to sing or play along in your key. ✂ Trim audio Keep the part you want. Unlike video, the cut lands exactly where you put it. » Change audio speed Faster or slower sound, at the same pitch.