BPM counter from the microphone
Measure the tempo of music playing in the room, on the radio or from another device. Press Listen, allow the microphone and wait a few seconds.
Drop audio or video files here
MP3, WAV, M4A, OGG, FLAC, MP4… one or many — analysed on your device, never uploaded
Listening
BPMTempo
BPMCandidates
Key (estimate)
—
Beat grid
Not sure? Tap along
Tap 4+ times on the beat.
Tempo over time
Results
| File | BPM | ½ / 2× | Conf. | Key (est.) | Length |
|---|
How it works
Listen mode keeps the last 12 seconds of microphone audio in memory and analyses it every second and a half with the same onset-and-autocorrelation engine used for files. The number shown is the median of the last five confident readings, so a single misheard bar doesn’t make it jump. Nothing is recorded or uploaded; when you press Stop the audio is discarded.
Rooms add echo and phones add automatic gain control, both of which blur drum hits. The tool asks the browser to switch echo cancellation, noise suppression and gain control off, which most desktop browsers honour. For the most reliable reading, get close to the speaker, turn the music up and wait for two or three readings to agree.
If the music has no clear drums, such as solo piano or an ambient pad, an automatic reading may never settle. Use the Tap button instead: tap along for eight or more beats and the median interval between taps gives the tempo.
Tips
- Move close to the speaker and turn it up
- Wait for 2–3 readings to agree
- Tap along (T key) for music without drums
Step by step
- Open your audio. Click Open files or drop one or more MP3, WAV, M4A, OGG, FLAC or video files onto the page. They are decoded in your browser and never uploaded.
- Read the tempo. The BPM appears with a confidence score and the top candidates. Use ½× or 2× if the result is half or double what you hear, or set a tempo range.
- Check the beat grid. Click anywhere on the waveform to play from there with a click on every beat. Nudge the grid by 10 ms if it is slightly early or late.
- Export. For several files, download the results table as CSV or TXT, or copy it to the clipboard.
FAQ
Are my files uploaded?
No. Files are decoded with your browser’s Web Audio API and analysed by JavaScript on your device. Nothing is sent to a server, so large files and unreleased tracks are fine.
Why does it say 64 when my song is 128 BPM?
Tempo has octaves: a beat at 128 BPM also repeats every two beats (64) and has a pulse on every eighth note (256). The detector picks the most likely level, but it can land on the half or double. Click 2× or ½×, pick another candidate, or choose a tempo range such as 80–160 so the result is always folded into it.
Which formats can I analyse?
Anything your browser can decode: MP3, WAV, M4A/AAC, OGG, Opus and FLAC in all modern browsers, AIFF in Safari, and the audio track of MP4, MOV and WebM videos. You can drop several files at once.