What does Audio Speed Changer do?
Tubelexity changes audio speed between 0.25x and 4x and calculates the resulting duration as original duration divided by speed. Preserve-pitch mode changes tempo without intentionally moving musical pitch; natural mode changes playback rate, so pitch moves with speed. Both modes export locally to MP3, WAV or M4A.
How to use Audio Speed Changer
- 1Choose a supported local audio file.
- 2Select a speed preset or enter a custom value from 0.25x to 4x.
- 3Choose Preserve pitch or Natural pitch change and check the resulting duration.
- 4Set export quality, process, preview and download.
Supported inputs and outputs
Inputs
MP3, WAV, M4A/AAC, OGG, WebM audio
Outputs
MP3, PCM WAV, AAC in M4A
Practical uses
- Slowing down speech practice
- Speeding up a voice memo
- Changing podcast listening tempo
- Creating a tape-speed sound
Browser and media limitations
- Tempo processing can create artifacts at extreme values.
- Natural mode deliberately changes pitch.
- Exports are re-encoded.
- Browser memory limits practical source length.
- Preview support depends on the browser codec even when FFmpeg can process the file.
How local processing works
Audio processing runs in this browser with lazy-loaded FFmpeg.wasm. The source and output are not uploaded to Tubelexity or a processing server.
Frequently asked questions
How is the new duration calculated?
The original duration is divided by the selected speed.
Can I speed up audio without making voices higher?
Yes. Choose Preserve pitch, which uses chained tempo filters.
What speeds are supported?
Safe custom values from 0.25x through 4x, with common presets.
What is natural pitch change?
Playback rate changes directly, raising pitch when faster and lowering it when slower.
Are files uploaded?
No. Processing stays in your browser.