Free tool
Key, BPM and chords. Of any song, free, in your browser.
How it works
01
Drop in a song
A finished track, a loop, a sample or a demo. Anything up to ten minutes.
02
It analyses the audio
The same tempo and harmony engines the SoundGen studio uses run on your device: beat tracking for the tempo, chroma analysis for the key and chords.
03
Read the chart
The key, the BPM, the chords that carry the song and the full progression with timings — ready to play along, remix or write over.
Questions
- Is it free?
- Yes, with no sign-up and no limit. The analysis runs on your computer.
- Is my audio uploaded?
- No. The file is decoded and analysed inside your browser tab and never leaves your device.
- How accurate is it?
- Tempo and key are reliable on most pop, electronic and rock music. Chords are best on clear harmony; dense mixes, heavy distortion and very jazzy voicings come out simplified. A song can also sit between relative keys (C major and A minor share notes), so check the chart by ear.
- Why is the BPM half or double what I expected?
- Tempo is ambiguous by a factor of two: a 140 BPM track can feel like 70. If the number looks off, halve or double it.
- What formats work?
- WAV, MP3, M4A/AAC, FLAC and OGG in most browsers. Safari does not decode OGG; use another format there.
More free tools
Know the key.
Now write in it.
The SoundGen studio puts a chord track on any clip, generates parts that follow it, and lets an AI producer arrange the rest.