UtilityKit

500+ fast, free tools. Most run in your browser only; Image & PDF tools upload files to the backend when you run them.

BPM Detector

Detect beats per minute from any audio file using Web Audio API. Or use the tap-tempo button.

About BPM Detector

BPM Detector analyzes uploaded audio files to determine their tempo in beats per minute (BPM). It works entirely in your browser using the Web Audio API — your music file never leaves your device. Upload an MP3 or WAV, click Detect BPM, and the tool analyzes the onset envelope to find the beat frequency. A tap-tempo fallback lets you tap along to any music to get an instant BPM reading.

Why use BPM Detector

  • Runs entirely in your browser — audio stays on your device
  • Fast analysis using Web Audio API
  • Tap-tempo fallback for any source
  • Shows half-time and double-time variants
  • No registration required
  • Fast analysis using the Web Audio API

How to use BPM Detector

  1. Upload an MP3 or WAV audio file
  2. Click 'Detect BPM'
  3. Wait for analysis (usually 1-3 seconds)
  4. Read the detected BPM value
  5. Or: tap the TAP button repeatedly in time with any music for tap-tempo BPM
  6. Upload an MP3 or WAV audio file via the upload area
  7. Click 'Detect BPM' to start onset analysis

When to use BPM Detector

  • DJs matching tracks by tempo
  • Musicians learning a song's tempo
  • Fitness apps syncing music to workout cadence
  • Music producers sampling or remixing
  • Dancers matching footwork to music BPM
  • DJs matching tracks by tempo for seamless mixes

Examples

Detect tempo of a house track

Input: 4-min MP3 house track at 124 BPM

Output: Detected 124 BPM with half-time 62 BPM and double-time 248 BPM options

Tap-tempo a live band performance

Input: User taps the TAP button 12 times in time with a live drummer

Output: Stable running average around 96 BPM after the first 6 taps

Trap beat with half-time feel

Input: WAV trap instrumental, perceived 70 BPM

Output: Detector reports 140 BPM; user clicks half-time to confirm 70 BPM is the intended tempo

Tips

  • For best accuracy, upload at least 30 seconds of audio — the longer the sample, the more confident the detected BPM.
  • If the result feels wrong, tap tempo a few bars yourself and compare; sometimes the algorithm picks the snare rather than the kick.
  • Hip-hop, drum-and-bass and trap often confuse single-pass detectors — always check the half-time variant.
  • Trim the song to a section with steady drums (no breakdown, no intro) before running detection.
  • Tap at least 8 times for a stable tap-tempo reading — fewer taps amplify timing jitter.
  • Live cues like clapping or stomping make great tap-tempo sources when you don't have an audio file handy.

Frequently Asked Questions

Is my audio file uploaded to a server?▾
No. Analysis happens entirely in your browser using the Web Audio API. Your audio file never leaves your device.
How accurate is the BPM detection?▾
The algorithm works well for music with a clear beat (electronic, pop, rock). It may be less accurate for complex jazz or classical music.
What file formats work?▾
Any audio format your browser supports: MP3, WAV, OGG, M4A, FLAC. The exact support depends on your browser.
What's tap tempo?▾
You tap a button repeatedly in time with the music. The tool averages the intervals between your taps to compute BPM. It works for any audio source — even live music.
Why does it show half-time and double-time?▾
Many songs can be perceived at different tempo 'layers'. Half-time is half the detected BPM (useful if the algorithm found the double-time), and double-time is twice the BPM.
What does 'envelope' mean in BPM detection?▾
The envelope is the smoothed amplitude over time. Peaks in the envelope (loud transients) indicate beats, and the spacing between peaks gives the BPM.
Will it work on a 1-second clip?▾
Clips shorter than ~10 seconds may not have enough beats for accurate detection. Longer clips (30+ seconds) give better results.
Can I detect BPM from a microphone?▾
The current tool works on uploaded files. Tap tempo is the best option for live audio.

Explore the category

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Glossary

BPM (beats per minute)
How many musical beats occur in one minute. The standard tempo measurement across DJing, fitness, music notation and audio production.
Tempo
The speed of music. Measured in BPM. Slow ballads sit around 60–80 BPM; club tracks usually 120–135 BPM; drum-and-bass 160–180 BPM.
Onset detection
An algorithm that finds the times at which note attacks (beats, hits, transients) occur in an audio signal.
Envelope
A smoothed curve of audio amplitude over time. Peaks in the envelope correspond to loud transients like kick-drum hits.
Autocorrelation
A signal-processing technique that compares a signal to delayed copies of itself to find repeating patterns — used here to find the beat period.
Web Audio API
Browser API for low-level audio processing. Used to decode audio files into raw samples for analysis.
Sample rate
Samples per second of audio data (typically 44.1 kHz or 48 kHz). Affects how much detail the analysis sees.
Half-time / double-time
Tempo perceptions where the felt beat is half or twice the detected pulse rate. Common in hip-hop, drum-and-bass and trap.