Speed Up or Slow Down Video in Your Browser
Make any video 2x faster, 1.5x, 1.25x or half-speed — audio pitch-corrected automatically, processed locally with nothing uploaded.
Change the playback speed of a video directly in your browser: speed it up 1.25x, 1.5x or 2x, or slow it down to half speed. The audio is retimed with pitch correction so voices stay natural instead of turning into chipmunks. Everything runs on your device — nothing is uploaded.
Choose a file or drop it here
🔒 Processed locally — never uploaded.
Long screen recordings and lectures beg to be watched faster; a too-quick tutorial sometimes needs the opposite. This tool re-times both the picture and the sound: choose 0.5x, 1.25x, 1.5x or 2x, and the audio is tempo-shifted with pitch correction so a 2x voice still sounds like a person, not a cartoon. Pick the speed, drop the file, download the result.
How it works
- Choose the speed first: 2x (default), 1.5x, 1.25x, or 0.5x slow motion.
- Pick a video from your device or drop it into the box — video and audio are re-timed together, with the audio pitch-corrected.
- Press the download button for your re-timed MP4.
Common uses
- Condense a long screen recording or lecture into half the watch time.
- Speed up a slow tutorial before sharing it with your team.
- Slow down a fast demonstration or sports clip to study the details.
- Tighten a meeting recording before archiving it.
Supported formats and limits
| Input | MP4, MOV, WebM, MKV, AVI (H.264, H.265/HEVC, VP8, VP9, MPEG-4) |
|---|---|
| Output | MP4 — H.264 video re-timed to the chosen speed + AAC audio with pitch-corrected tempo |
| Speed choices | 0.5x (slow motion) - 1.25x - 1.5x - 2x (default) |
| Maximum file size | 500 MB (in-browser memory limit) |
| Where it runs | Entirely in your browser (WebAssembly) — keeps working offline once loaded |
Frequently asked questions
Is my video uploaded while changing speed?
No. The re-timing runs inside your browser using FFmpeg compiled to WebAssembly. Your file never leaves your device.
Will the audio sound like a chipmunk at 2x?
No. The audio is processed with a tempo filter that changes speed without changing pitch, so voices stay natural — the same technique podcast and video players use.
Does the video duration change?
Yes — that is the point. A 10-minute video at 2x becomes 5 minutes; at 0.5x it becomes 20 minutes. Video and audio stay perfectly in sync.
Can I use a custom speed like 1.7x?
The current version offers 0.5x, 1.25x, 1.5x and 2x — the speeds people actually use. A free-form speed field is on our roadmap.
Is there a size limit?
Files up to 500 MB are supported. Processing takes roughly 1.5x the video length, since both streams are re-encoded.
Is this free?
Yes — free, no signup, no watermark, no queue. Processing happens on your device, so there is nothing for us to meter.