How to speed up or slow down a video
Last updated 2026-10-20
To speed up a video, select the clip and set its speed above 1x. At 2x it plays twice as fast and takes half the time. For slow motion, set the speed below 1x, but only footage shot at a high frame rate, such as 120 fps, stays smooth. A time lapse is the same idea at a high multiple on long footage.
Speed up a video
Speed is a multiplier. A 40-second clip at 2x takes 20 seconds. At 4x it takes 10. The new length is the footage you keep divided by the speed.
Speed up the dull stretch, not the whole video. The walk to the door, the drawing, the loading bar. Leave the moment people came for at normal speed. To fast forward one part, split the clip first so that part is its own clip.
Two mistakes to avoid. A sped-up voice is hard to follow, so cut the pauses instead of speeding up the talking. And a faster clip is shorter, so check the timeline for a gap afterwards.
Slow motion and frame rate
Slow motion needs spare frames. Footage shot at 30 frames per second has 30 pictures each second. Played at half speed, an editor has only 15 real pictures per second to show, and the motion turns choppy. Shoot at a higher frame rate first, then slow it down.
Apple says an iPhone records Slo-mo at 1080 HD and 240 fps from the back camera by default, and that Video mode offers 24, 25, 30, 60 or 120 fps depending on the model. Use the table to pick.
| Slowed to | Shoot at least |
|---|---|
| 0.5x | 60 fps |
| 0.25x | 120 fps |
| 0.125x | 240 fps |
Time lapse from long footage
A time lapse squeezes minutes or hours into seconds. You can capture one directly: Apple's iPhone Camera has a Time-lapse mode that records at set intervals. Or you can record normal video and speed it up.
Do the sum before you commit. An hour of footage at 16x still runs 3 minutes 45 seconds. A 30-second time lapse from an hour needs 120x. Trim to the part that matters first, or use a capture mode.
Speed ramps, reverse and audio
A speed ramp changes speed inside one clip, such as normal speed easing into slow motion at the key moment. Woven does not do this, because speed is one value per clip. You can split a clip and give each piece its own speed, but the change is a jump, not an ease. Woven has no reverse or freeze frame either.
iMovie on Mac does more here. Hold R and drag to select a range, choose Slow or Fast, and tick Smooth for a gradual change. It also has a Reverse checkbox. On Mac, Photos can play a video at half speed if it was captured at 60 fps or more, and at quarter or one-fifth speed if it was captured at 120 fps or more. Apple's QuickTime Player guide lists trim, split, rotate and flip for editing, not speed.
Audio follows the clip. iMovie lowers the pitch when you slow a clip and raises it when you speed one up, unless you tick Preserve Pitch. Woven has no pitch control, so for sped-up footage mute the clip and put music under it.
Change speed in Woven
Speed applies to video clips. The toolbar Speed menu offers 0.5x, 1x, 1.5x and 2x. For anything else, ask in chat: any speed above 0, up to 16. Below 0.25x, Woven's AI agent gets a warning to check the result. A clip's length is its kept footage divided by speed, so you can also ask it to fit a clip into a set time.
Ask in chat
- Speed up the second clip to 4x and mute it.
- Slow the last shot to 0.5x.
- Fit the drone shot into 8 seconds.
- Make the sunset section a 16x time lapse.
Or do it by hand
- 1Import. Choose Add, then Video, or drag the file onto the timeline.
- 2Split. Put the playhead where the change starts and press ⌘B. For a middle section, split again where it ends, so that part is its own clip.
- 3Set the speed. Select the clip, open Speed in the toolbar and choose 0.5x, 1x, 1.5x or 2x. Ask in chat for other values.
- 4Handle the sound. Press M to mute the clip, or use Volume to lower it.
- 5Close the gap. Press Space to play it back. If a faster clip left a gap, drag the later clips left.
Common questions
Open it in an editor with a speed control, select the clip and choose a speed above 1x. iMovie and Woven both have one. Apple's QuickTime Player editing guide covers trimming, splitting, rotating and flipping, not speed.
Shoot at 60 fps or higher, then set the clip below 1x. For 30 fps playback, 120 fps footage stays smooth down to 0.25x. Slowing 30 fps footage that far looks choppy.
Either record with a Time-lapse mode, such as the one in the iPhone Camera, or speed up normal footage. In Woven, chat accepts up to 16x.
A speed ramp changes a clip's speed partway through, for example fast then slow. Woven has one speed per clip, so it cannot ramp. iMovie can, using a selected range and its Smooth option.
Yes. The audio plays faster with the picture. iMovie raises the pitch unless you tick Preserve Pitch. In Woven, mute a sped-up clip and add music.
Split the clip at both ends of that part, then change the speed of the middle piece only. Each piece keeps its own speed.
Sources
- Change clip speed in iMovie on Mac - Apple Support, checked October 19, 2026
- Change and enhance a video in Photos on Mac - Apple Support, checked October 19, 2026
- How to edit videos on your iPhone, iPad, or Mac - Apple Support, checked October 19, 2026
- Record a video with your iPhone camera - Apple Support, checked October 19, 2026
- Change video recording settings on iPhone - Apple Support, checked October 19, 2026
- QuickTime Player User Guide - Apple Support, checked October 19, 2026
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