Song Key Finder

Song Key Finder

The Song Key Finder estimates the musical key and scale of a track — for example G major or C♯ minor — entirely in your browser. Drop in an audio file and the tool decodes it, builds a chromagram of which pitch classes are most present, and matches that profile against every major and minor key to find the most likely fit, returning the key plus its Camelot wheel code for harmonic mixing. Knowing a song's key is invaluable when you are layering parts over an AI-generated track, harmonically mixing in a DJ set, transposing a sample to fit, or writing a topline that sits in tune. It pairs naturally with the BPM detector: together, key and tempo are the two numbers that let you blend tracks cleanly. Unlike tools that upload your audio, this one analyzes everything locally with the Web Audio API, so unreleased material stays private. Under the hood it uses a Goertzel-based chromagram and the Krumhansl-Schmuckler key profiles — a well-established approach — but key detection is genuinely hard: tracks that modulate, that are heavily percussive, or that sit ambiguously between a relative major and minor can read as a neighboring key. Treat the result as a strong estimate and a starting point, and confirm by ear, especially before committing to a transposition. For DJs, the Camelot code makes compatible keys obvious — adjacent numbers and the A/B switch are your friends. Like the rest of the hub it is free, requires no signup, and runs entirely in your browser, so even unreleased material stays on your machine.