Free Song Key Finder

Find the musical key of any song. Drop in an audio file and Solmi detects the key (like A Minor or C Major), its Camelot code for DJ mixing, and the BPM — no upload, no signup, and your audio never leaves your device. Supports MP3, WAV, M4A, AAC, OGG, and FLAC.

Turn your song into a music video

Features

  • Automatic key detection from any audio file (all 24 major and minor keys)
  • Camelot wheel code for harmonic DJ mixing (e.g. A Minor = 8A)
  • Detects the BPM (tempo) alongside the key
  • Runs fully in your browser — audio never uploaded to a server
  • Free with no signup, then turn your song into a beat-synced music video

Frequently Asked Questions

How does this key finder work?

Upload an audio file and Solmi analyzes it directly in your browser — it decodes the audio, builds a chromagram (how much energy the song has at each of the 12 pitch classes), and matches that profile against standard major and minor key templates (the Krumhansl–Schmuckler method). The best-matching of the 24 keys wins. Nothing is uploaded to a server.

How accurate is the detected key?

Very reliable for most popular music, which stays in one key with clear harmony. Treat it as a strong estimate: heavily chromatic music, key changes mid-song, detuned recordings, or ambient tracks without clear harmony can be ambiguous. A common near-miss is the relative key — A Minor and C Major share the same notes — so if the result feels off, try its relative first.

What is a Camelot code?

The Camelot wheel maps each of the 24 musical keys to a simple code — a number 1–12 plus 'A' for minor keys or 'B' for major keys (A Minor is 8A, C Major is 8B). DJs use it for harmonic mixing: songs whose codes are identical, one number apart, or the same number with the other letter blend smoothly together.

What's the difference between a key and a scale?

The key names the tonal center and whether it's major or minor — for example, A Minor. The scale is the set of notes that key uses. A song 'in the key of A Minor' mostly builds its melody and chords from the A natural minor scale. Key finders report the key; the matching scale follows from it.

Can I find the key of a song without uploading it anywhere?

Yes — that's exactly how this tool works. The analysis runs entirely in your browser using the Web Audio API, so the audio file never leaves your device. It also means there's no file-size wait: detection starts immediately.

Is the song key finder free?

Yes, completely free with no signup. Once you know your song's key and BPM, you can turn the track into a beat-synced music video with Solmi's AI music video generator — also free to start.

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