Free tool
Speed up or slow down a video
Pick a video and speed it up to 4× or slow it down to 0.25×. The sound keeps its pitch, so voices don't turn squeaky or deep. It all happens in your browser: the video is never uploaded to a server, you don't need an account, and there's no watermark.
- Never uploaded
- No sign-up
- No watermark
- 0.25× to 4×
Opening the video…
Mark a part you don't want: it is taken out and the rest is joined.
Shortcuts: Space plays or pauses · ← → one frame · Shift + ← → one second · I and O set the start and end
Runs on mediabunny and gifenc and, when needed, FFmpeg's AAC encoder and the LAME MP3 encoder. Licences
How to change a video's speed
Choose the video
Tap Choose a video and pick an MP4, MOV or WebM file from your phone or computer. It opens right away, because it isn't uploaded anywhere.
Pick the speed
2× is already selected. To go faster, pick 3× or 4×; for slow motion, 0.75×, 0.5× or 0.25×. Press play to see and hear how it turns out before you save.
Save the video
Tap Change speed and save. When it's done, download it or, on a phone, save it to your gallery with Save or share.
What you can do
Speed up to 4×
Make a timelapse of a recipe or a drive, or shorten a lecture or a tutorial: at 2× it runs half as long.
Slow motion down to 0.25×
Slow a movement down to 0.75×, 0.5× or 0.25× to watch it in detail.
Voices keep their pitch
The sound is stretched or squeezed without changing its pitch, so nobody sounds like a chipmunk or a robot. Or remove the sound, if you'd rather.
Try it before you save
The preview plays at the speed you picked, so you see and hear the result first.
Trim in the same step
Cut the start, the end or a stretch in the middle, switch to vertical 9:16, or rotate the video before saving.
Your video stays on your device
Your browser changes the speed. There's no upload, no processing queue to wait in, and no copy of your video on any server.
Questions
How do I speed up a video?
Choose the video: 2× is already selected. For faster, pick 3× or 4×, then tap Change speed and save. A 10-minute video at 2× runs 5 minutes.
Will the slow motion look smooth?
It depends on how it was recorded: the page doesn't invent frames, it shows each one longer. A video recorded at 30 frames per second plays at 15 at 0.5×. For smooth slow motion, record at 60 or 120 frames per second, as many phones can.
Does the voice change pitch?
No. The sound is fitted to the new speed with its pitch kept, in the preview and in the saved video. At the extremes (0.25× or 4×) voices can sound less natural; if you don't like it, tick Remove the sound.
Can I speed up just one part of a video?
The speed applies to everything you save. To speed up one stretch, mark its start and end first and save that part; the rest stays in your original video.
Is my video uploaded to the internet?
No. The file is read and processed inside your browser, on your own device, and the page never sends it to a server. That's why it starts right away, even when the video is several GB.
Does the video lose quality?
It's re-encoded at a quality close to the original's. When it's sped up, it keeps the original's frame rate (30 frames per second, for example), so movement looks normal.
Does it work on iPhone and Android?
Yes: in Safari on iPhone, in Chrome on Android, and on a computer in an up-to-date Chrome, Edge, Safari or Firefox. To keep the video in your phone's gallery, tap Save or share and choose Save Video.
Which formats does it take?
It opens MP4, MOV (like the iPhone's), WebM and MKV videos, and saves as MP4, MOV or WebM. You can also save the result as an animated GIF: at 2×, 60 seconds of the original fit in a 30-second GIF.
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