At a glance
- Cost
- 100% free, no account
- Speeds
- Half speed (0.5×) to double speed (2×)
- Pitch
- Preserved with Signalsmith Stretch, or shifted like a turntable
- Saves
- MP3 or WAV
- Privacy
- Stays on your device
Changing the speed
- Load your audio.
- Set the rate with the slider or a preset button. Below 1× is slower, above 1× is faster, and the new duration is shown instantly.
- Pitch on or off: keep Keep original pitch ticked for natural voices, or untick it for a record-player effect.
- Render and download as MP3 or WAV.
Two kinds of speed change
Time-stretching (pitch preserved)
Here the tool uses Signalsmith Stretch, a modern frequency-domain engine that stretches or compresses time while keeping every note at its original pitch. It copes well with chords and full mixes, not just single voices. It's the right choice for:
- getting through podcasts, audiobooks and recorded classes faster (1.25×–2×),
- practising difficult musical passages at 60–80% speed,
- dictation and language learning at a gentler pace,
- fitting narration or music to an exact running time.
Resampling (pitch follows speed)
Like spinning a turntable faster or slower: speeding up raises the pitch and slowing down lowers it. It's the classic sound of "nightcore", "sped up" and "slowed" edits, with zero stretching artefacts.
Handy speed settings
| Rate | Effect on a 60-minute file | Good for |
|---|---|---|
| 0.5× | becomes 2 hours | Transcribing music note by note |
| 0.75× | 1 h 20 min | Practice, language listening |
| 1.25× | 48 min | Comfortable faster listening |
| 1.5× | 40 min | Lectures and familiar podcasts |
| 2× | 30 min | Skimming recordings |
To change the musical key without touching the tempo, use the Key Changer instead.
Common questions
Will voices sound strange when sped up?
Not with Keep original pitch enabled. Speech stays natural up to around 1.75×, and remains understandable at 2×.
How do I make a slowed-down version of a song?
Untick Keep original pitch and choose about 0.8×. The song gets slower and deeper at the same time.
What's the allowed range?
From 0.5× to 2×, in 0.05 steps.
Is the file uploaded?
No. Everything is rendered in your browser.