Video Speed Changer
Upload a video, adjust the speed and output size, and download the result as WebM. Everything runs in your browser.
Drop a video here
or click to browse — MP4, WebM, MOV, and more
About this tool
Upload any video, pick a playback speed from 0.25x all the way up to 4x, scale down the dimensions if you want a smaller file, then export it as a downloadable WebM. The preview updates live so you can hear and see what it'll look like before exporting. Scaling to 50% typically cuts file size by around 75% since you're reducing both width and height. Everything runs in your browser using the Canvas and MediaRecorder APIs. Nothing gets uploaded.
Seven speed presets from 0.25x to 4x
Scale output to 100%, 75%, 50%, or 25% of original size
Aspect ratio is always preserved when scaling
Three export quality levels to control bitrate
Audio is included in the exported file
Runs entirely in your browser, nothing leaves your device