Slowed + Reverb & Sped Up Maker

Drop a song you already have and turn it into the edits that fill TikTok, YouTube and Instagram: slowed + reverb, sped up, or nightcore. Three one-click presets do the work, and fine sliders let you dial in the exact feel. Everything runs in your browser with the Web Audio API — your file is decoded, processed and exported entirely on your device, and is never uploaded to any server.

“Slowed + reverb” is the dreamy, late-night sound: the track is slowed down so the pitch drops and the groove stretches out, then reverb is added so it feels spacious and far away. Our Slowed + Reverb preset sets the speed to about 0.85×, adds a medium room reverb and a touch of bass, and you can push the reverb higher or the speed lower for a deeper, more washed-out vibe. It is the look-and-feel people search for as “slowed reverb maker” or “make a song slowed”.

Sped Up is the opposite energy — the version that makes a chorus hit faster and brighter. The Sped Up preset runs around 1.25× with only a hint of reverb, which is exactly the “sped up” sound popular on short-form video. Nightcore goes further: classic nightcore is faster and higher-pitched at once, so that preset speeds the track up with the pitch riding along, giving the bright, energetic, slightly chipmunk-y feel the genre is known for.

Two pitch modes are available. Linked (tape/vinyl) mode is the default and powers all three presets: changing the speed also changes the pitch, just like slowing down a record — this is what gives slowed edits their signature lower pitch and nightcore its higher one. Independent (time-stretch) mode is for power users: it lets you change the tempo without changing the pitch, or shift the pitch in semitones without changing the tempo, using an in-browser time-stretch engine.

A live player lets you hear the result before you export. Press play and the slowed/reverb effect is applied in real time; move the reverb, room-size, speed or bass sliders and the sound updates as you listen, with a waveform showing your position. When you are happy, hit Download to render the final audio offline (faster and cleaner than realtime) and export it as a small, shareable MP3 or a lossless WAV. The result shows the before and after length so you know how long the edit runs.

Because the tool only processes a file you provide, there is no music library, no royalty-free catalogue and no way to paste a streaming or YouTube link — that keeps everything copyright-clean and private. Share means sharing the tool, not your audio: the Share button copies the page link (or opens your device share sheet), while your track stays on your device. For best results start from a clean, reasonably high-quality file; very long or very large files are processed in your device’s memory, so a shorter clip is smoother on phones.