Change Video Speed
Make a timelapse or a slow-motion version of a video.
Drop your video here
MP4, MOV, WebM, MKV, AVI…
×
Uses ffmpeg.wasm: about 30 MB is downloaded the first time, then cached. Processing speed depends on your device — a 1-minute 1080p clip takes roughly 1–3 minutes.
● Your video is processed locally in your browser and never uploaded. Large files need a recent computer with enough memory.
How it works
Video timestamps are multiplied (setpts filter), so 2× plays twice as fast and 0.5× in slow motion. Audio is time-stretched with ffmpeg's atempo filter, which keeps voices at their natural pitch. Slowing down doesn't create new frames: below 0.5× motion gets choppy unless the original was filmed at a high frame rate.