Song Key Finder
Work out what key a song is in, with its Camelot wheel code for harmonic mixing. Analysed in your browser using chroma and Krumhansl-Schmuckler profiles.
What is the Song Key Finder?
The ByteTools Song Key Finder estimates the musical key of a track. It measures how much energy sits on each of the twelve pitch classes, folding harmonics back onto their fundamentals so overtones do not skew the picture, then compares that fingerprint against the twenty-four major and minor key profiles from Krumhansl's probe-tone experiments.
- Harmonic-summed chroma so overtones do not pull the answer toward the wrong key
- Krumhansl-Schmuckler profiles correlated against all 24 major and minor keys
- Camelot wheel code for harmonic mixing, plus relative and parallel keys
- Four ranked runners-up with match strengths, not just a single verdict
- Pitch class bar chart showing what the analysis actually measured
- Fully local - the audio never leaves your device
How to use the Song Key Finder
- 1
Drop a song onto the box, or click to browse.
- 2
Click Find the Key and wait while the track is decoded and analysed.
- 3
Read the estimated key, its Camelot code and the relative key.
- 4
Check the runners-up and the pitch class chart if the match strength is low.
- 5
Copy the key with the copy button to paste into your library or set list.
About the Song Key Finder
The ByteTools Song Key Finder estimates the musical key of a track. It measures how much energy sits on each of the twelve pitch classes, folding harmonics back onto their fundamentals so overtones do not skew the picture, then compares that fingerprint against the twenty-four major and minor key profiles from Krumhansl's probe-tone experiments.
You get the key, its Camelot wheel code for harmonic mixing, the relative and parallel keys, four runners-up with their match strengths, and a bar chart of the twelve pitch classes so you can see what the analysis actually heard. DJs, producers looking for a sample that fits, and anyone learning to play along by ear will find it a useful starting point.
This is an estimate, not an authority. Key detection compares statistics, so it can confuse a key with its relative minor or major, and modal, atonal or heavily processed music defeats it. Everything runs in your browser through the Web Audio API - the track is never uploaded.
Frequently asked questions
How accurate is automatic key detection?
It is a good first guess rather than a definitive answer. Clear tonal music with obvious chords is usually right, but the most common failure is naming the relative major or minor instead - C major and A minor share all seven notes, so statistics alone cannot always separate them. Always check it against your ear.
What is the Camelot wheel and how do I use it?
It renames each key as a number from 1 to 12 with A for minor and B for major, so compatible keys sit next to each other. Tracks mix smoothly with the same code, one step up or down the number, or the same number in the other letter. C major is 8B and its relative A minor is 8A.
Why did it pick the relative minor instead of the major key?
Because the two keys use identical notes, and only emphasis tells them apart. If the chart shows strong energy on the major tonic and the analysis still says minor, trust the chord you hear the song resolve to. The runners-up list almost always has the right answer near the top.
Does it work on any genre?
It works best on music with clear harmony - pop, house, techno, most singer-songwriter material. It struggles with rap over a single loop, modal jazz, drone, noise, and anything without stable pitched content. Very heavy distortion also smears the pitch classes.
Is my music uploaded for analysis?
No. The file is decoded and analysed entirely by code running in your browser tab, so nothing is sent to a server. Unreleased tracks and private demos stay on your own machine.
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