WebToolArcAudio Speed Changer
Change tempo with pitch preserved, use tape-style linked pitch, or combine speed with a custom pitch shift. Preview locally, loop a difficult phrase, solve speed from target duration or BPM, then render and compare the exact WAV result without uploading your audio.
Audio Speed Changer — tempo, pitch & practice
Keep pitch while changing tempo, choose tape-style speed that moves pitch naturally, or combine speed with an independent semitone shift. Preview before rendering, loop a hard phrase, solve by duration or BPM, then compare the exact WAV result.
1. Load audio
2. Choose tempo & pitch behavior
3. Solve a speed instead of guessing
4. Preview, render & compare
Repeat-use settings
Recent rendered summaries
What changed in this Audio Speed Changer
Keep pitch, tape-style, or custom pitch
Modern speed changers separate tempo from pitch because podcast listening, transcription and music practice usually need natural voices or an unchanged musical key. Tape mode stays available when linked speed-and-pitch is the effect you actually want.
Preview is not the same as export
The original player can preview speed immediately with browser pitch preservation. Custom independent pitch is heard from the rendered result. The result player is the exact local WAV created by this page, so you can A/B before downloading.
A–B loop for practice and transcription
Click the waveform to seek, mark A and B at the playhead, then loop only the difficult passage while choosing a useful tempo. Loop markers affect practice preview; export still renders the complete source.
Target duration and BPM solve
If you need a 12-minute recording to become 8 minutes, solve the rate directly instead of dragging a slider. Musicians can also use known original and target BPM values; the page does not pretend to detect BPM automatically.
Browser-local privacy
Selected audio is decoded and rendered in browser memory. The settings link does not contain audio, filenames, local recipes, or loop points. The 80 MB cap is a responsiveness policy, not an audio-format limit.
Why WAV only
This route exports deterministic 16-bit PCM WAV without bundling a large codec stack. It does not claim to preserve the source codec, tags, MP3 bitrate or container metadata. Use WAV when you want a transparent handoff for another editor or encoder.
Quality boundary
Pitch-preserving time stretch can create warble, transient smearing or phasing at extreme rates. Speech and sustained music use different overlap profiles, but neither is marketed as studio mastering or a substitute for specialized offline DSP.
Speed and pitch math
Tape-style pitch shift is 12·log₂(speed) semitones. Keep-pitch aims for zero semitone change. Custom mode shifts by the selected semitone amount while independently targeting the chosen output duration.