⏩

Free Video Speed Changer

Speed up or slow down a video from 0.25× to 4×, with pitch-corrected audio. Great for slow-motion and timelapse. Runs entirely in your browser.

No file size limitFiles stay privateNo login requiredFree forever

Drop files here, or click to browse

MP4, WebM, MOV, AVI, Video no file size limit

Browse files

Your files never leave your device. All processing happens locally in your browser.

Speed up or slow down a video (0.25×–4×), with pitch-corrected audio. Runs entirely in your browser.

Optimize for your platform

Make a Slow-Motion Video Speed Up a Video / Timelapse Speed Up a Tutorial or Lecture Speed-Ramp a Clip for Social Slow a Video Down to Analyse It

How It Works

Speeding up or slowing down a video means re-timing both the picture and the sound. This does it with FFmpeg in your browser, keeping the audio pitch natural.

1
FFmpeg.wasm loads once
The WebAssembly build of FFmpeg (~30 MB) downloads on first use and is cached afterwards.
2
You pick a speed
From 0.25× (slow motion) to 4× (fast forward / timelapse feel). Your file stays in the browser.
3
Video and audio are re-timed
The video uses setpts to change frame timing; audio uses chained atempo filters that stretch time without altering pitch, so voices stay natural.
4
You download the result
The re-timed MP4 is offered for download and previewed in-page.