Shift Pitch
Shift audio pitch up or down by semitones without changing playback speed.
100% in your browser — files never leave your device
Transpose audio to any key
Pitch shifting has many practical uses: transposing a backing track to match a vocalist's range, moving an instrument recording to a different key for a mix, or creating harmonies and special effects. Standard pitch changes — like resampling — alter the duration as well as the pitch. That is rarely what you want.
This tool chains three FFmpeg filters — asetrate, aresample, and atempo — to change pitch while keeping playback duration constant. The input is first normalized to 44100 Hz, then the sample rate is adjusted to produce the desired pitch shift, then resampled back and time-stretched to compensate. The range is ±12 semitones (one full octave).
Everything runs in your browser with FFmpeg.wasm. No server, no upload, no account.
Frequently asked questions
How does pitch shifting work without changing speed?
The tool uses a three-step FFmpeg filter chain: asetrate changes the interpreted sample rate to shift the pitch (higher sample rate = higher perceived pitch), aresample converts the audio back to the original sample rate (which stretches/compresses the waveform), and atempo adjusts the playback speed to compensate so the duration stays the same. The result is a pitch shift at constant speed.
What is a semitone?
A semitone is the smallest interval in standard Western music — one step on a piano keyboard. There are 12 semitones in an octave. Shifting by +12 semitones doubles the frequency (raises by one octave); shifting by -12 halves it. Smaller shifts like ±2 semitones are used to transpose a recording to a different key.
Is my audio uploaded anywhere?
No. All processing runs entirely in your browser using FFmpeg.wasm. The WASM binary (about 25 MB) downloads from a CDN on first use and is then cached. Your audio never leaves your device.
Will pitch shifting affect the quality?
The asetrate/aresample/atempo approach involves resampling, which introduces some minor quality trade-off at extreme shifts. For moderate ranges (±7 semitones), the result is generally clean. Using a lossless output format (WAV or FLAC) preserves as much quality as possible from the processing chain.
Why does the first run take longer?
FFmpeg.wasm (about 25 MB) downloads on first use and is cached by your browser. After that, subsequent operations start immediately without another download.