Speed up or slow down audio playback without changing pitch.
Audio Speed Changer changes how fast a clip plays while keeping its pitch where it started, using time-stretching instead of simply resampling the file. You choose a speed multiplier and the tool renders a new file whose duration scales accordingly. The detail people miss most: this is not the same as setting a raw playback-rate value on an audio track, which raises or lowers pitch together with speed, the way a vinyl record sounds different when played off-speed. Extreme speed settings can introduce audible artifacts such as warble or a stuttering texture; how noticeable this is depends on the source material and how far the speed is pushed from 1x.
A concrete input and expected output from the current implementation.
Input
60-second voice recording, speed set to 1.5x
Expected output
40-second audio file, same voice pitch as the original
Duration scales inversely with the speed factor (60s / 1.5 = 40s); the tool uses time-stretching rather than resampling to hit that new length, so pitch is unaffected.
Simple resampling (playing samples faster or slower) speeds up audio but also raises or lowers its pitch, the same way a vinyl record sounds different off-speed. This tool instead uses time-stretching, which changes duration while leaving pitch intact.
You set a speed multiplier (for example 0.75x or 2x). The tool computes the new duration as original length divided by that factor, processes the audio to hit it, and exports the result. There is no separate pitch control; pitch is held constant by design, not adjustable independently within this tool.
No. Pitch preservation is the whole point of this tool: it uses time-stretching rather than resampling, so a voice sped up to 1.5x still sounds like the same voice at the same pitch, just talking faster.
You can get close by picking a speed factor equal to original length divided by target length, but expect the actual output to land within a fraction of a second of that target rather than exactly on it, so double-check the final duration before relying on it.
The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.
Convert CSV data into structured JSON arrays or objects with automatic type detection.
Transform JSON arrays and objects into downloadable CSV spreadsheet format.
Convert YAML configuration files to JSON format with validation and formatting.
Parse XML documents and convert them to equivalent JSON structure with attributes.
Convert tab-separated values to comma-separated format with proper escaping.
Convert numbers between binary, octal, decimal, and hexadecimal bases.