Change Your Audio's Speed
Speed up or slow down any audio file from 0.25x to 4x — keep the pitch natural or go full tape-speed effect, all processed privately in your browser.
Drag and drop an audio file here, or click to browse
MP3, WAV, M4A, OGG, or FLAC — up to 100MB
Upload an audio file to change its speed
About the Audio Speed Changer
This free tool speeds up or slows down any audio file, from a gentle 0.75x to an extreme 4x. Choose pitch-preserving tempo change powered by FFmpeg's atempo filter, or the classic tape-speed effect where pitch rises and falls with speed. Everything runs locally in your browser via WebAssembly — nothing is uploaded.
Features:
- Speed range from 0.25x (slow motion) to 4x (fast forward)
- Two distinct modes: pitch-preserving tempo or classic tape-speed effect
- Export as lossless WAV or compressed MP3
- Privacy-first — speed changes happen entirely on your device
How to Change an Audio File's Speed
- Upload an MP3, WAV, M4A, OGG, or FLAC file
- Pick a speed preset or fine-tune it with the slider
- Choose keep-pitch or classic tape-effect mode, and an output format
- Click Change Speed, then preview and download the result
Frequently Asked Questions
Is this audio speed changer really free?
Yes. There's no signup, no watermark, and no limit on how many files you process — everything runs in your browser.
Does my audio get uploaded to a server?
No. Speed changes happen entirely locally using FFmpeg and the Web Audio API, both running in your browser. Your file never leaves your device.
What audio formats can I upload?
MP3, WAV, M4A, OGG, and FLAC are supported, up to 100MB per file.
What's the difference between keeping pitch and the tape effect?
Keep-pitch mode changes tempo only — a voice stays at its natural pitch whether you slow it to 0.25x or speed it to 4x, using FFmpeg's atempo filter. The tape effect changes pitch and speed together, exactly like adjusting a physical tape or record's playback speed: faster means higher-pitched (the classic "chipmunk" or nightcore sound), slower means a deep, dragging pitch.
Can I remove pitch shift after using the tape effect?
Not from the tape-effect output itself — pitch and speed are linked together in that mode by design. If you need the original pitch back, reprocess the original file using keep-pitch mode instead.
Does speeding up audio lose quality?
Keep-pitch mode processes audio losslessly internally and can export as lossless WAV with no quality loss. Choosing MP3 output applies standard MP3 compression, similar to any MP3 encoder. The tape effect is a pure playback-rate change and doesn't degrade audio quality either — the output format you choose is what determines final quality.
Privacy
Your audio is processed entirely in your browser using WebAssembly and the Web Audio API. It is never uploaded, stored, or seen by our servers.