BPM detector
The tempo of a track, read from where the sound gets louder.
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or click to choose from your deviceAccepted: MP3, M4A, AAC, WAV, OGG, OGA, OPUS, FLAC, WEBA, MP4, M4V, WEBM, MOV, MKV
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This tool runs entirely in your browser. Nothing is uploaded, nothing is stored, and you can even turn off your internet connection before you start.
Example
Example: a 128 BPM house loop and a 174 BPM drum and bass loop
Two 30-second drum loops exported from a music app — kick on every beat, snare on 2 and 4 — one made at 128 BPM, one at 174. Each is added with Expected tempo on Anything; the drum and bass loop again with Fast.
- Under each reading come the half and double tempos — 63.8 / 255.3 BPM for the house loop — and a confidence, strong here.
- Anything writes the answer between 70 and 180 BPM, so the drum and bass loop reads 173.9; its line “could also be: 87.0 / 347.8 BPM” gives the half-time count.
- With Fast, only 100–220 BPM is searched, and the same loop reads 173.9 BPM again.
| Loop | Expected tempo | Reading | Beat | Bar (4/4) |
|---|---|---|---|---|
| 128 BPM house | Anything | 127.7 BPM | 0.470 s | 1.880 s |
| 174 BPM drum and bass | Anything | 173.9 BPM | 0.345 s | 1.380 s |
| 174 BPM drum and bass | Fast · 100–220 BPM | 173.9 BPM | 0.345 s | 1.380 s |
Both tempos within half a beat per minute. Use the beat line to set a delay or cut a video to the music: at 127.7 BPM a beat lasts 0.470 s and a 4/4 bar 1.880 s.
How it works
- Add a track — MP3, M4A, WAV, FLAC, or a video, whose sound is read.
- Leave the expected tempo on “anything” unless you know the track is unusually slow or fast.
- Read the answer: the tempo, the length of a beat and of a bar, and the half and double tempos.
- Use the beat length to set a delay, a loop or a video edit to the music.
Frequently asked questions
- How accurate is it?
- On music with an audible beat, usually within a fraction of a beat per minute. It reads a whole track at once, so a recording that speeds up or slows down — a live take, an old record — gets an average rather than a true answer.
- Why does it sometimes say half or double what I count?
- Because both are true of the same music: 75 and 150 line up with the same beats. Each delay is scored together with its double and triple to pick the one people would tap, and the other readings are printed under it.
- Does it work on speech or a podcast?
- Not meaningfully. It needs repeated attacks — drums, chords, a strummed guitar. Speech has no steady beat to find.
- Why does a slow song show double its tempo?
- Because 70 and 140 fit the same beats when the hi-hat plays every eighth note, and on Anything the answer is written between 70 and 180 BPM: such a 70 BPM loop reads 139.5. Choose Slow (40–100 BPM) and it shows 70.0. Fast (100–220 BPM) does the same for fast songs: a 200 BPM click reads 100.0 on Anything and 200.0 on Fast.
- How long is one beat?
- 60 seconds divided by the tempo: at 120 BPM a beat is 0.500 s and a 4/4 bar 2.000 s; at 128 BPM, 0.469 s and 1.875 s. Both are printed for the tempo found, ready for a delay time or a video edit.
- Is my music uploaded?
- No. It is decoded and measured in your browser, and nothing is sent anywhere.