Time-Stretch Audio to Target BPM — No Pitch Change
A free BPM changer for audio files that adjusts tempo without affecting pitch. Match tracks to a specific BPM for DJing, music production, or practice — processed entirely in your browser.
Match any track to your target tempo without changing pitch
Drop your audio file here
or click to browse
Upload multiple files to stretch them all to the same target BPM
| File | Original BPM | Ratio | Status |
|---|
Features
How to Change BPM Without Changing Pitch
- Upload your audio file (MP3, WAV, FLAC, OGG, M4A)
- BPM is auto-detected — correct manually or use Tap Tempo if needed
- Set target BPM using quick buttons, genre presets or manual input
- Preview the time-stretched result in real-time
- Click Download — processing happens in your browser
Why Use Our BPM Time-Stretch Tool
No software to install, no account required, no file uploads. Auto-detect BPM, choose your target tempo from genre presets or enter manually, preview in real-time, and download. Built for DJs, remixers, and producers who need tracks at the right tempo.
Frequently Asked Questions
What is time-stretching?
Time-stretching changes the tempo (speed) of audio without changing its pitch. Unlike simple speed change that produces a "chipmunk" or "slowed" voice effect, time-stretching preserves the original tonality while only adjusting the tempo.
How accurate is the auto BPM detection?
The algorithm detects BPM with 90-95% accuracy for most music with a clear beat. If the detection is off, you can manually enter the correct BPM, use Tap Tempo, or use the half/double buttons to fix common octave errors (e.g. 60 detected instead of 120).
What happens with extreme tempo changes?
For changes within ±40% (ratio 0.6–1.4x), quality remains excellent. For larger changes, the algorithm chains multiple processing stages — quality may degrade slightly. A color indicator shows the expected quality for your ratio.
How is this different from the Audio Speed Changer?
The Speed Changer is speed-first: you set a playback rate (e.g. 1.5x). This tool is BPM-first: you set a target BPM (e.g. 128) and the speed ratio is calculated automatically. It also includes genre presets, batch mode, and is designed specifically for DJ and remix workflows.
Are my files uploaded to a server?
No. All processing happens locally in your browser using FFmpeg WebAssembly. Your audio files never leave your device, ensuring complete privacy.
Can I process multiple files at once?
Yes. Switch to Batch mode, add multiple files, set a single target BPM, and click Process All. Each file's BPM is auto-detected and individually stretched to match the target.
We can — and it's free! Just send us a quick message with your idea. If you'd like to discuss it in detail, leave your email and we'll get back to you. You can stay anonymous.
