MotionShine01 / Drop
Choose your video
Drag in the file. It plays from your own disk and never goes online.
Free tool
Video speed changer.
Speed up a long screen recording or slow down a fast one, from 0.25x to 4x, and save it as an MP4. It runs in your browser, so nothing is uploaded.
This runs in your browser. Your files are never uploaded.
How it works
Three steps, nothing to install.
02 / Pick
Choose the speed
Pick a speed from 0.25x to 4x, and keep or remove the sound. The page shows the new length.
03 / Save
Change and download
The video is re-encoded at the new speed as an MP4. Play it, then download it.
Questions
Good to know.
Is my video uploaded?
No. It is changed in this tab with your browser, so the file never leaves your computer.
What happens to the sound?
It plays at the new speed too, so voices sound higher when sped up and lower when slowed down. Choose Remove the sound if you plan to add music or a voice-over.
Is slow motion smooth?
Frames are repeated to fill the time, so a 0.25x video looks stepped rather than smooth. Smooth slow motion needs footage recorded at a high frame rate.
Does it lower the quality?
Every frame is re-encoded as H.264, so there is a small loss, as with any re-encode.
Can I speed up only part of a video?
Not here. Cut the part out first with the video trimmer, change its speed, then join the parts with the video merger.
Which browsers work?
Current Chrome, Edge and Safari, which can encode H.264 video. The file has to be one your browser can play.