Demo Editor

Free tool

Speed up (or slow down) a video

Make a slow screen recording snappy, or slow a moment down. Pick 0.25× to 4× for the whole video or just a part of it, and voices keep their pitch instead of sounding like chipmunks.

Clipper
Media
Drop videos to start
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V1
A1
Space playB split under the mouse⌫ deleteCtrl+Z undo← → step a frame⇧Z fitDrag a clip to move it, its edges to trim. Hold Ctrl to stop snapping.

How to do it

  1. 1. Drop your video

    Drag it onto the editor. To change the speed of only one part, press B at its start and end to split it off.

  2. 2. Pick a speed

    Click the clip (or select several) and choose a speed in the toolbar: 0.25×, 0.5×, 1.5×, 2× or 4×. ⌘] and ⌘[ step it up and down. The clip gets shorter or longer on the timeline.

  3. 3. Export

    Press Export for an H.264 MP4. The sound is sped up with the picture and keeps its pitch, so a voice at 2× just sounds faster.

The keys you already know

Hover a clip and press B to split it right under the mouse, ⌘B to split at the playhead, ⌫ to delete and ⌘Z to undo. Space plays, the arrow keys step a frame, ⌘J joins what you split. On Windows, Ctrl does what ⌘ does. On a phone, tap clips to select them and drag a selected one.

One picture, three sounds

V1 holds the picture and keeps its clips end to end, so deleting one closes the gap. Up to three audio tracks sit under it for the clips’ own sound, music and a voiceover, each placed wherever you like.

Clips for your next promo video

Select the clips you cut and press Add to library: each one is saved to your Demo Editor project with a note on how to use it, and the next video you make can use exactly that footage. It’s the one step that needs an account.

Your videos stay with you

Everything is decoded and encoded in your browser. The edit is kept in this browser too, so a reload brings it back. The export is an H.264 MP4 at up to 1080p that plays everywhere.