How to Slow Down a Song Without Changing the Key
Slowing a song without affecting pitch requires time-stretching. This guide covers the fast browser-based approximation using sound-goods, the proper method using Audacity, and when each is the right choice.
Music teachers, language learners, and transcribers need to slow audio without the pitch dropping — so a guitar solo stays in the same key, a spoken phrase stays intelligible, or a foreign word remains recognizable at half speed. The technique is time-stretching, which separates pitch from tempo.
Method 1 — Browser-based with pitch compensation (fast, good for speech)
- At 0.75× → set Pitch to +5
- At 0.8× → set Pitch to +4
- At 0.5× → set Pitch to +12
Method 2 — True time-stretching in Audacity (best for music)
- Open Audacity (free, all platforms)
- File → Import → Audio — select your file
- Select all: Ctrl+A / Cmd+A
- Effect → Change Tempo
- Set Percent Change: −25 for 0.75×, −20 for 0.8×, −50 for 0.5×
- Click OK — Audacity processes using the SBSMS algorithm (pitch-neutral)
- File → Export → Export as MP3 at 192kbps
Slow down your audio — pitch compensation included
Browser-based, no upload, continuous slider from 0.25× to 4×.
Open Speed Changer →Method comparison
| Method | Best for | Music quality | Speech quality | Setup |
|---|---|---|---|---|
| sound-goods + pitch compensation | Speech, podcasts, language learning | Acceptable at modest speeds | Excellent | None — browser |
| Audacity Change Tempo | Music transcription, all content | Good–Excellent | Excellent | Desktop install |
| VLC (playback only) | Listening — no export | Good | Good | VLC installed |
Use cases
Music transcription
Slow a fast guitar solo to 0.7× while keeping pitch to transcribe notes accurately. Use Audacity's Change Tempo for dense musical passages.
Language learning
Slow native speaker audio to 0.8× with +4 semitone compensation. The slight quality trade-off is imperceptible for speech, and you can hear individual phonemes much more clearly.
Instrument practice
Slow complex piano or guitar passages to 0.5× with Audacity to hear each note separately, while keeping them in the correct octave for identification.
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