Is the BPM detector free?

Yes. ToolKnit BPM Detector is 100% free with no signup, no watermarks, and no file uploads to any server.

How does BPM detection work?

The tool decodes your audio file using the Web Audio API, analyzes the waveform for onset events (energy peaks), and calculates the average interval between beats to determine the BPM.

Is my audio file uploaded to a server?

No. All processing happens locally in your browser. Your audio file never leaves your device.

What audio formats are supported?

MP3, WAV, OGG, FLAC, M4A, AAC, and any format your browser can decode through the Web Audio API.

How accurate is the BPM detection?

The algorithm is accurate for most rhythmic music (pop, rock, electronic, hip-hop). Complex or irregular rhythms may show approximate results. You can verify with the tap tempo feature.

Back to ToolKnit

Blog Tool Tales

BPM Detector — Find Any Song’s Tempo

Upload an audio file and detect its BPM instantly in your browser. Waveform visualization, beat markers, and audio info — 100% private, no server upload.

MP3 / WAV / OGG Waveform + Beats Tap Tempo Verify No Signup

Drop your audio file here

or click to browse — MP3, WAV, OGG, FLAC, M4A

How to detect BPM

Three steps — find the tempo of any song.

Upload your audio

Drag and drop or browse for any MP3, WAV, OGG, FLAC, or M4A file. The file stays in your browser — nothing is uploaded to a server.

Analyze the waveform

The Web Audio API decodes your file and runs onset detection to find energy peaks. The interval between peaks gives the BPM.

Get BPM & verify

See the detected BPM, waveform with beat markers, and audio details. Use Tap Tempo to verify by ear, or play the audio back.

Why use this BPM detector?

100% Private — No Server Upload

Your audio file is decoded and analyzed entirely in your browser using the Web Audio API. Nothing is sent to any server. Safe for copyrighted music, unreleased tracks, and personal recordings.

Waveform & Beat Visualization

See the audio waveform with detected beat markers overlaid. The visual feedback helps you confirm that the detected tempo matches the actual rhythm of the song.

Tap Tempo Verification

Not sure the detected BPM is right? Play the audio and tap along. The tap tempo counter shows your manual BPM so you can compare it against the algorithm’s result.

Complete Audio Info

Get duration, sample rate, channel count, and file size alongside the BPM. Everything you need to catalog your music library or prepare tracks for DJing.

Pro Tips

● Electronic and pop tracks give the most accurate results because of their steady, prominent beats.
● For rubato or live recordings, the detected BPM is an average — use tap tempo for a more human reading.
● If the BPM seems double or half the expected value, the algorithm may have locked onto eighth notes or half notes. Divide or multiply by 2.
● Pair with the Metronome to practice at the detected tempo.