How to use the BPM finder
- Drop a song file on the box, or press it and choose a file. MP3, WAV, M4A and FLAC work in current browsers.
- Read the result. The big number is the tempo in beats per minute. A whole number like 128 means the measurement was within 0.15 of it; the exact figure appears next to it.
- Look at the confidence chip. High means a steady beat stood out clearly. Medium or Low means you should check it.
- Switch to half or double time if your software counts the beat differently. Press Use next to the value you need.
- Check by ear. Play the preview with the click track, or tap along on the tap pad and compare.
How the tempo finder works
The tempo finder doesn’t use an AI model or a song database. It measures the sound itself, the same way on every file.
First, the song is decoded and mixed to mono at 22,050 samples per second. The analysis then looks at short slices of sound, about 86 per second, and notes where new energy appears: drum hits, strummed chords and plucked notes. That gives an onset curve, which rises at every new note.
Next, it compares the curve with delayed copies of itself. When the delay equals the time between beats, the peaks line up. The finder scores every tempo from 60 to 200 BPM this way, with a mild preference for tempos near 120, where most popular music sits.
Finally, it lays a beat grid over the onsets and fits it to the actual peaks. That pins the tempo down to a fraction of a BPM and places the click track on the beat.
Reading the result: confidence, half and double time
| What you see | What it means | What to do |
|---|---|---|
| High | One tempo clearly beats every unrelated one | Use it |
| Medium | Likely right, but other tempos came close | Check it with the click track |
| Low | No tempo stood out | Tap along and trust your taps |
| “Tempo seems to change” | The four quarters of the song disagree by more than 4% | Tap along in the part you need |
| “No clear beat found” | Ambient music, speech or silence, with no steady pulse to measure | Tap along, if there’s a beat you can feel |
| Half and double values | The same pulse counted at a different level | Pick what your software expects |
Half and double time aren’t errors. A house track at 124 BPM can be felt at 62, and a ballad at 70 can be counted at 140. DJ software usually wants the faster reading for dance music. The finder also tells you when a tempo 2/3 or 3/2 of the result scored almost as well, which is common in songs in 6/8 or with a swing feel.
To use the number, type it into the BPM field of your DJ software or the project tempo of your DAW. Songs recorded without a click track drift a little, so a band recording may read 97.6 rather than a round 98. For songs longer than 80 seconds, the sections line shows the tempo of each quarter, so you can see how much it moves.
Check the result by tapping
Press Preview to play the analyzed copy of the song with a click on every beat. If the clicks drift ahead, the real tempo is a little lower. If they fall behind, it’s higher. You can start the preview at any of four parts of the song.
The tap pad gives a second opinion. Tap along with the song, or focus the pad and press T, and after nine taps the page compares your tempo with the analysis. For longer tapping sessions and a metronome check, use the tap tempo tool.
Can it read Spotify or YouTube songs?
No. Streaming services and video sites don’t give web pages access to their audio, so there’s nothing for the finder to analyze, and a pasted link only gives it the address. Protected downloads, such as Apple Music files ending in .m4p, can’t be decoded in a browser either.
What works: MP3s you bought, songs you ripped from your own CDs, stems and bounces from your DAW, and recordings you made. If you only have a streamed song, play it on another device and tap along.
Which files work
MP3, WAV and M4A (AAC) open in every current browser. FLAC opens in Chrome, Edge and Firefox, and in Safari on a Mac. OGG depends on the browser. Some video files work too, if the browser can read their sound track.
Files can be up to 150 MB and 10 minutes long. The limit exists because the browser keeps the whole decoded song in memory while it measures it. For a long DJ mix or a concert recording, cut out the part you need with the MP3 cutter first, then drop that part here.
On an iPhone or iPad, the file picker opens the Files app. Songs in the Music app’s library aren’t available to web pages, so save a copy of the file to Files first.