How to speed up or slow down a video (audio stays in pitch)

Speeding up or slowing down video is a creative superpower — turning a 30-minute tutorial into a 10-minute watch, or making smooth slow-motion from 60fps footage. The tricky part is keeping audio natural.

Why pitch matters

Naive speed changes make voices sound like chipmunks. Our Video Speed Changer uses time-stretching that preserves pitch, so sped-up speech stays intelligible.

Speed guide

• 0.25×–0.5× — slow motion (best from 60fps source)
• 1.25×–1.5× — tutorials and lectures, still natural
• 2×–4× — time-lapses and quick reviews

How to do it

Upload your video, drag the speed slider, download. The whole thing runs in-browser with ffmpeg — your footage never leaves your device.