Speed Up Video or Slow It Down – Video Speed Changer
Speed up video clips from 1.05× to 4×, or slow them down to as little as 0.25×, and save the result as a new file. Voices keep their natural pitch, so a lecture at 1.5× still sounds like the speaker rather than a cartoon. Common speed-ups such as 2× on 30 fps footage re-time the frames without re-encoding, which is fast and lossless. Everything runs in your browser.
- Runs on your device
- WebCodecs · GPU
- FFmpeg
- Works offline
Updated
Drop your videos here
How to speed up a video
Step 1: Drop one or more videos on the box above.
Step 2: Drag the Speed slider: above 1× is faster, below 1× is slower. 2× halves the length; 1.25× trims a fifth off a long talk.
Step 3: Choose the Audio: Keep pitch for natural voices, Change pitch for the sped-up tape sound, or Mute.
Step 4: Press Apply and download the faster video. The result card shows the new length and whether the frames were copied or re-encoded.
Good to know
Settings explained
- Speed
- Below 1× slows down, above 1× speeds up.
- Audio
- Keep pitch: Natural voices
- Change pitch: Like a tape
- Mute
- Quality
- Only used when a stream has to be re-encoded. Compatible streams are copied with no quality loss.
- Faster: Smaller file, quickest export
- Balanced: Good quality at a sensible size
- Best quality: Largest file, slowest export
Formats
Batch-friendly: add many files and they are processed one after another — if one fails, the rest still finish.
How it runs
- Hardware video engine
- Video is decoded and encoded by your device’s media hardware through WebCodecs — usually several times faster than real time.
- FFmpeg (when needed)
- Older formats and a few filters use FFmpeg compiled to WebAssembly. It downloads once (about 31 MB) the first time it is needed and is cached for offline use.
How long will my video be? Speed vs new length
The new length is the old length divided by the speed. The table shows a 10-minute recording at the speeds people use most; the same ratios apply to any clip.
| Speed | New length | Typical use |
|---|---|---|
| 1.25× | 8:00 | Lectures, meetings and tutorials that still need to be followed |
| 1.5× | 6:40 | Screen recordings and walkthroughs |
| 2× | 5:00 | Fast forward through slow action, cooking, setup steps |
| 4× (maximum) | 2:30 | Very quick recaps; beyond this, use the timelapse maker |
| 0.5× | 20:00 | Half speed, for a slower look at a movement |
Speed up a video without changing the pitch
Playing sound faster normally raises its pitch, which is why fast-forwarded voices squeak. Keep pitch uses time-stretching instead: the audio is cut into tiny overlapping slices that are packed closer together, so the speech gets shorter while every voice stays at its own pitch. It works best on speech between about 1.1× and 2×.
Change pitch speeds the sound up like a tape played fast, the classic chipmunk effect. Mute drops the soundtrack, which suits silent fast-forward shots or clips that will get music later.
Is the video re-encoded? It depends on the speed
When the sped-up frame rate stays between 10 and about 60 frames per second, ProMedia just gives every frame a new timestamp: a 30 fps clip at 2× plays at 60 fps with every original frame intact, nothing re-encoded. Outside that range the frames are thinned out (or repeated, when slowing down) to a steady rate and encoded once, at the Quality set under Advanced settings. The audio is always rebuilt.
| Source | 1.5× | 2× | 3× | 4× |
|---|---|---|---|---|
| 24 fps (film, many cameras) | Lossless (36 fps) | Lossless (48 fps) | Re-encoded at 24 fps | Re-encoded at 24 fps |
| 30 fps (most phones) | Lossless (45 fps) | Lossless (60 fps) | Re-encoded at 30 fps | Re-encoded at 30 fps |
| 60 fps (sport, gaming) | Re-encoded at 60 fps | Re-encoded at 60 fps | Re-encoded at 60 fps | Re-encoded at 60 fps |
Change video speed on iPhone, Android, Windows or Mac
This video speed changer works the same in every current browser. Built-in options exist, but they differ a lot.
iPhone
The Photos app can only adjust the slow part of clips filmed in Slo-mo; it cannot speed up a normal video. iMovie can, inside a project. Here, open the page in Safari and pick the clip from Photo Library.
Android
Some gallery editors, such as Samsung’s, include a speed control. Otherwise open this page in Chrome; the faster copy is saved to Downloads.
Windows
Clipchamp has a speed setting for each clip on its timeline. For a quick 1.5× version of a recorded meeting, drag the file into the browser here.
Mac
QuickTime Player can play faster but cannot save a sped-up file. Drop the video into Safari or Chrome here to export one.
Tips & troubleshooting
Faster than 4×? The timelapse video maker goes up to 32× and keeps a smooth output frame rate.
For smooth slow motion, use the slow motion video maker: it blends frames instead of repeating them.
Speeding up a music track or podcast without video? The audio speed changer handles MP3, M4A and WAV.
Zoom or Teams recording? Try 1.25× or 1.5× with Keep pitch, then shrink the result with the video compressor before sharing.
Video Speed Changer FAQ
How do I speed up a video just a little bit?
Set the slider to 1.1× or 1.25×; it moves in steps of 0.05. Keep Audio on Keep pitch and the change is hard to notice, but a 20-minute talk loses two to four minutes.
How do I speed up a video without changing the pitch?
Leave Audio on Keep pitch. The sound is time-stretched rather than played faster, so voices stay at their natural pitch at any speed from 0.25× to 4×.
Can you speed up a video in the iPhone Photos app?
No. Photos can trim and adjust the slow section of Slo-mo clips, but it has no speed control for normal videos. Open this page in Safari, pick the clip and set the speed; save the result back to Photos.
What is the difference between speeding up a video and a time-lapse?
A speed-up stays watchable as normal footage, usually up to 4×, and keeps the sound. A time-lapse compresses a long scene by 8×, 30× or more, is normally silent and plays at a steady frame rate. The timelapse video maker is built for that.
How do I speed up a video and save it?
Pick the speed here and press Apply. The new file downloads with the speed in its name, for example clip-2x.mp4, and plays at that speed in any player.
Is your video uploaded anywhere?
No. Your video is processed by your own browser on your own device. There is no server that receives files, so nothing is uploaded, stored or shared. You can even switch to airplane mode once the page has loaded.