Whether you are learning a fast guitar solo, transcribing a tricky vocal run, or just want to enjoy a song at a relaxed tempo, slowing music down is incredibly useful. The key is to keep the pitch the same so the song does not sound deeper or out of tune. FreeSoundTools' Speed & Pitch tool does exactly that, for free, directly in your browser.
How to Slow Down a Song
- Open the Speed & Pitch tool.
- Upload your audio file (MP3, WAV, M4A, OGG, etc.).
- Move the Speed slider to your desired tempo. For example, 0.75x plays at 75% of the original speed.
- Leave the Pitch slider at 0 (no change) to keep the original key.
- Click play to preview. When satisfied, save the result as MP3 or WAV.
How It Works
The tool uses a time-stretching algorithm that separates tempo from pitch. In the old cassette-tape days, slowing a tape also lowered the pitch. Digital time-stretching avoids this by analyzing the audio in small windows and re-synthesizing it at the new speed without altering the frequency content.
Common Use Cases
- Instrument practice: Slow a fast passage to 50-70% speed, learn the notes, then gradually increase the tempo.
- Vocal training: Hear every syllable clearly at a slower pace before singing along at full speed.
- Transcription: Slow down speech or music to catch every word or note for notation.
- Dance choreography: Practice moves at half-speed before going full tempo.
Tips for Best Results
- Speeds between 0.5x and 0.9x usually sound natural. Below 0.5x, you may notice some processing artifacts.
- If you also want to change the key (e.g., lower it for your vocal range), adjust the Pitch slider independently.
- Start with a high-quality source file for the cleanest result.
Privacy
Your files never leave your device. All processing happens in the browser using Web Audio APIs. Nothing is uploaded to any server.
FAQ
Does slowing down music change its pitch?
Not with a time-stretching algorithm. FreeSoundTools separates speed and pitch controls, so you can slow a track down while keeping the original key intact.
How slow can I go?
You can go as low as 0.25x (quarter speed). Below 0.5x the audio may sound slightly processed, but it remains usable for practice.
Do I need to create an account?
No. The tool works without sign-up. Your files are processed in the browser and never uploaded to a server.