Audio
Change Audio Speed
Speed up or slow down any audio, 0.5x to 2x — entirely in your browser. Your audio is never uploaded; it never leaves your device.
This tool runs FFmpeg directly in your browser using WebAssembly — there is no server, no account, and no upload. Your audio file is read from your disk, its tempo adjusted in a background thread, and the result is ready to download immediately. Nothing is ever sent over the network — you can confirm this yourself by watching the Network tab in your browser's developer tools while processing runs.
Drag the speed slider or pick a preset from 0.5x to 2x. Leave “Preserve pitch” on to keep voices and music sounding natural at the new speed, or turn it off for the classic tape/vinyl-style pitch shift — faster and higher, or slower and deeper.
How to Use
- 1
Drop an audio file onto the uploader or click to browse.
- 2
Drag the speed slider or click a preset (0.5x–2x).
- 3
Leave "Preserve pitch" on for natural-sounding results, or turn it off for a tape/vinyl-style pitch shift.
- 4
Choose your output format and click "Apply Speed". Download the result when it's ready.
Frequently Asked Questions
Is my audio uploaded to a server?
No. Processing runs entirely in your browser using FFmpeg compiled to WebAssembly. Your audio never leaves your device — verifiable in your browser's Network tab during a run.
What does "Preserve pitch" do?
On (default), only the tempo changes — voices and music keep their natural pitch. Off, pitch shifts along with speed, like a tape or vinyl record at the wrong speed.
What speed range is supported?
0.5x to 2x, in fine steps or via quick presets.
What output formats are supported?
MP3, WAV, M4A, AAC, OGG, and FLAC — the same encoding as the Audio Converter.
Does this reduce audio quality?
The speed change itself is clean. Choose WAV or FLAC for no additional loss; lossy formats like MP3 have the same small re-encoding loss as any conversion.