Change Video Speed
How to change the speed of a video
- Click the box above or drop your video onto it.
- Pick a speed. Under 1× is slow motion, over 1× is faster.
- Choose whether to keep the audio in step, then click Change speed.
Frequently asked questions
Does the audio go up in pitch?
No. The audio is stretched or squeezed in time while the pitch is left where it is, so voices still sound normal at 1.5×. Choose Remove the audio if you want it silent.
Will slow motion look smooth?
It will be as smooth as the original frames allow. Slowing a 30 fps clip to a quarter speed shows each frame four times as long, so movement looks stepped. Truly smooth slow motion has to be filmed at a high frame rate.
How long will the result be?
The original length divided by the speed: a 60 second clip at 2× becomes 30 seconds, and at 0.5× it becomes two minutes.
Why does it have to re-encode?
Because every frame gets a new timestamp, which means rewriting the video stream. The file is saved as MP4 with H.264 at a high quality setting.
Is my video uploaded?
No. The conversion runs in your browser with FFmpeg compiled to WebAssembly. The first use downloads the converter (about 30 MB); your file never leaves your device.