Audio Playback Rate & Pitch Shifter
Combines playback speed s with a pitch offset p semitones: effective rate = s × 2^(p/12). Both duration and pitch change; the exported frame count is ceil(input frames / effective rate).
About this audio playback rate & pitch shifter
Change playback rate and pitch in semitones, with the resulting duration shown by the output.
How this tool works
Combines playback speed s with a pitch offset p semitones: effective rate = s × 2^(p/12). Both duration and pitch change; the exported frame count is ceil(input frames / effective rate).
- Download the example file and select it in the file input.
- Set the visible controls to: Speed (0.25–4×) = 2; Pitch (semitones) = 0
- Click “Process locally”.
- Download the result and inspect: czoa-audio-pitch-speed.wav — PCM16; 48000 Hz; 2 channels; 36000 frames; 880 / 1320 Hz
Worked example
Scenario: Example file: /examples/audio-stereo.wav; Download the example file and select it in the file input. Set the visible controls to: Speed (0.25–4×) = 2; Pitch (semitones) = 0 Click “Process locally”. Download the result and inspect: czoa-audio-pitch-speed.wav — PCM16; 48000 Hz; 2 channels; 36000 frames; 880 / 1320 Hz
Sample input:
Illustrative output:
Limits and verification
Speed is 0.25–4× and pitch is −24 to +24 semitones. This uses sample playback-rate conversion, not independent time stretching or formant preservation. PCM16 WAV is resampled at 48 kHz.
Examples demonstrate an expected workflow; they do not prove every input or every branch of an external specification. Check important results with an independent source before using them for money, security, compliance, safety, or irreversible file changes.
Browser processing boundary
Tool input is processed by code running in the browser and is not intentionally sent to a CZOA processing API. The page can still request ordinary site assets, analytics, or advertising when those services are enabled. Browser extensions and managed-device software remain outside this tool's control.
Relevant references
These references govern or help explain the format, protocol, or calculation used here. Listing a reference does not claim certification or complete implementation of every optional feature.
- W3C Web Audio API 1.0 — browser decoding and offline rendering
- Microsoft RIFF/WAVE PCM and WAVEFORMATEXTENSIBLE
Content owner: CZOA Tools · Last reviewed: 2026-09-15 · Review methodology
How to use it
- Download the example file and select it in the file input.
- Set the visible controls to: Speed (0.25–4×) = 2; Pitch (semitones) = 0
- Click “Process locally”.
- Download the result and inspect: czoa-audio-pitch-speed.wav — PCM16; 48000 Hz; 2 channels; 36000 frames; 880 / 1320 Hz
Frequently asked questions
How does Audio Playback Rate & Pitch Shifter process the signal or file?+
Combines playback speed s with a pitch offset p semitones: effective rate = s × 2^(p/12). Both duration and pitch change; the exported frame count is ceil(input frames / effective rate).
How can I reproduce the Audio Playback Rate & Pitch Shifter example?+
Example file: /examples/audio-stereo.wav; Download the example file and select it in the file input. Set the visible controls to: Speed (0.25–4×) = 2; Pitch (semitones) = 0 Click “Process locally”. Download the result and inspect: czoa-audio-pitch-speed.wav — PCM16; 48000 Hz; 2 channels; 36000 frames; 880 / 1320 Hz
What limits apply to Audio Playback Rate & Pitch Shifter?+
Speed is 0.25–4× and pitch is −24 to +24 semitones. This uses sample playback-rate conversion, not independent time stretching or formant preservation. PCM16 WAV is resampled at 48 kHz.
What does browser-isolation evidence establish for Audio Playback Rate & Pitch Shifter?+
Recorded browser requests contained no selected-audio payload while the fixture rendered and downloaded WAV. This is evidence for the tested-browser tool-value path, not an absolute offline or no-network claim about page resources, extensions, or other environments.