Video Speed Changer
Speed up or slow down videos from 0.1× to 10.0× directly in your browser. Real-time speed preview, audio pitch preservation, clip trimming, and instant MP4/WebM export with 100% client-side privacy.
Speed Up or Slow Down Video in 3 Steps
Upload Video
Select or drop any MP4, WebM, MOV, MKV, or AVI video file. All processing is 100% private in your browser.
Choose Speed & Audio
Pick a quick preset (0.25× to 8.0×) or use the fine-tuning slider. Toggle audio muting or pitch preservation.
Export & Download
Click Change Video Speed to encode your high-definition video and download it immediately to your device.
Speed Multiplier & Audio Reference
Guidelines for selecting optimal speed factors and audio handling for your video projects.
| Speed Factor | Motion Effect | Recommended Audio | Ideal Use Case |
|---|---|---|---|
| 0.25× – 0.5× | Smooth Slow Motion | Keep (Pitch Shift) or Mute | Sports highlights, dramatic action shots, product reveals, dance analysis |
| 0.75× | Subtle Slowdown | Keep (Pitch Correct) | Tutorial clarity, speech comprehension, detailed motion reviews |
| 1.25× – 1.5× | Brisk Pacing | Keep (Pitch Correct) | Presentations, webinars, educational lectures, walkthroughs |
| 2.0× – 4.0× | Fast Forward | Mute Audio | Cooking recipes, coding sessions, art timelapses, routine walkthroughs |
| 4.0× – 10.0× | Hyperlapse / Timelapse | Mute Audio | Long journeys, construction logs, sunset/cloud timelapses, screen recordings |
Video Speed Changer — Frequently Asked Questions
Does changing video speed upload my file to a server?
No. The video is played by your browser, each frame is redrawn on a canvas at the new speed and recorded with the built-in MediaRecorder API. Audio is routed through the Web Audio API on your device. Nothing is sent anywhere.
What is the difference between "Pitch Correct" and "Pitch Shift"?
Pitch Correct keeps voices at their natural pitch, so sped-up speech doesn't sound like a chipmunk and slowed speech doesn't sound deep. Pitch Shift lets the pitch change with the speed, like a record played too fast or too slow. Mute drops the audio entirely — recommended above 2× where any audio becomes hard to follow.
Can I speed up just one section of the video?
Yes. Use the Trim start and end sliders in the source pane to choose the segment first; only that range is exported at the new speed.
Why did I get WebM when I selected MP4?
MP4 (H.264) recording depends on the browser: Chrome, Edge and Safari support it, Firefox records WebM only. If MP4 isn't available the tool falls back to WebM so you still get a playable file — the output stat shows the real format.
How long does processing take?
Processing runs in real time at the output speed. A 60-second clip at 2× takes about 30 seconds; at 0.5× it takes two minutes. Keep the tab in the foreground — browsers throttle background tabs and may stall the recording.
Which input formats are supported?
Anything your browser can play: MP4 (H.264), WebM and Ogg work everywhere; MOV works in Chrome and Safari; MKV and AVI only when they contain a browser-decodable codec. If the preview stays black, convert the file to MP4 first.