Make a slowed and reverb edit of a song in your browser
This slowed and reverb maker turns a song file you have into the dreamy, late-night version you know from short videos and playlists: played a little slower, so the voice and the key drop, and washed in a long reverb. One click gives the classic sound; the sliders let you set the exact speed, the size of the space and how much of it you hear. A Nightcore button does the opposite — faster and higher.
You can hear every change straight away: the live player runs the whole song with the current speed and reverb while you move the sliders. When it sounds right, the tool renders the edit at full quality and saves it as MP3, M4A, WAV, FLAC or OGG. It all happens in your browser — the song is not uploaded anywhere.
How to use the Slowed + Reverb Maker
- Drop an audio file — MP3, WAV, M4A, OGG, FLAC or WebM — onto the box. It must be a file on your device; links are not supported.
- Keep Slowed + reverb for the classic edit (0.85×, hall reverb, warm bass) or choose Nightcore (1.25×, a touch of room).
- Press play on the Live preview and adjust Speed, Reverb space, Reverb length and Reverb amount while it plays.
- Set Pitch to “Keep the original pitch” if you want it slower without the deeper voice.
- Pick a format and press Make slowed + reverb, listen to the result and download it.
Slowed + Reverb Maker features
Classic tape-style slowdown
Speed and pitch change together, like a turntable at the wrong speed: 0.85× is about 2.8 semitones lower. A windowed-sinc resampler keeps it clean.
Or keep the key
WSOLA time-stretching slows the tempo while the pitch stays put, for a relaxed version in the original key.
Three generated reverbs
Hall (long and dark), plate (smooth and bright) or room (short), made from impulse responses generated in your browser — no sampled spaces, no licence questions.
Live preview
The whole song plays with the current settings, and changes are heard immediately.
Nightcore too
One click for the sped-up, higher version: 1.25× with a short room reverb.
Settings that give the classic sound
The pitch change in semitones is 12 × log₂(speed). Below about 0.75× voices start to sound unnatural, which some edits use on purpose; the tool goes down to 0.5×.
| Style | Speed | Pitch change | Reverb | Extra |
|---|---|---|---|---|
| Slowed + reverb (default) | 0.85× | −2.8 semitones | Hall, 3.2 s, 35% | Warm bass |
| Heavier slowed | 0.80× | −3.9 semitones | Hall, 4–5 s, 40–50% | Warm bass |
| Light slowed | 0.90× | −1.8 semitones | Plate, 2 s, 25% | — |
| Nightcore | 1.25× | +3.9 semitones | Room, 0.8 s, 10% | — |
| Sped up | 1.15× | +2.4 semitones | Off or light | — |
Why there is no “paste a YouTube link” box
Many slowed and reverb sites offer to fetch a song from a video link. This one deliberately does not: downloading audio from streaming platforms breaks their terms of service and, for most commercial music, copyright law. Use a file you own, recorded yourself, licensed, or that is offered for download by its creator.
Slowing a song and adding reverb does not make it “no copyright”. The edit is still based on the original recording and composition, so uploading it publicly can lead to copyright claims, muted videos or takedowns. For your own listening it is fine; to publish, use music you have the rights to, or royalty-free tracks whose licence allows edits. This is general information, not legal advice.
How the edit is made
For the classic sound, the song is resampled — every sample is read 0.85 times as fast — with the same windowed-sinc resampler as the Audio Speed Changer. With “keep the original pitch”, it is time-stretched instead. The reverb is convolution with a generated stereo impulse response, as in Add Reverb to Audio, mixed with an equal-power balance; the optional warm bass is a gentle low shelf. The result is held under −0.3 dBFS so it never clips, then encoded. To cut the best part afterwards, use the Audio Cutter.
Slowed + Reverb Maker FAQ
How do I make a slowed and reverb song?
Drop the song file here, keep the Slowed + reverb style, check it in the live preview, then press Make slowed + reverb and download the MP3.
What speed is best for slowed and reverb?
Most edits use 0.8× to 0.9×. 0.85× is a good starting point; go lower for a heavier, darker feel.
Can I paste a YouTube or Spotify link?
No. The tool only works with files on your device, because downloading from streaming services breaks their terms and often copyright law.
Does slowing and adding reverb make a song copyright-free?
No. The edit is still a version of the original recording. Publishing it needs the rights holder’s permission unless the licence allows it.
How do I make nightcore?
Choose Nightcore: the song plays 1.25× faster and about four semitones higher, with a short room reverb.
Is my song uploaded?
No. Decoding, effects and encoding all happen in your browser.