Change Video Speed Online Free
Speed up or slow down any video from 0.25x to 4x. Real-time preview, powered by FFmpeg. Your files never leave your device.
How It Works
Upload Video
Drag and drop your video or click to browse. Supports MP4, WebM, and MOV formats up to 500 MB.
Adjust Speed
Use the slider or preset buttons to set your desired speed from 0.25x (slow motion) to 4x (fast forward).
Preview
Watch a real-time preview of your video at the selected speed before processing.
Download
Process and download your speed-adjusted video. The output file plays at the new speed in any video player.
Why Use Our Video Speed Changer?
The only video speed tool that processes everything in your browser. No uploads, no privacy concerns, no limits.
Complete Privacy
All processing happens in your browser using WebAssembly. Your video is never uploaded to any server.
Powered by FFmpeg
Uses the same FFmpeg engine trusted by professionals worldwide, running entirely in your browser via WebAssembly.
No Software Needed
Works in any modern browser on any device. No downloads, no plugins, no sign-ups required.
Free & Unlimited
No watermarks, no file count limits, no daily caps. Process as many videos as you need, completely free.
Frequently Asked Questions
The video speed changer supports MP4, WebM, and MOV files. MP4 is the most widely compatible format and recommended for best results. The output format matches your input file.
No. All processing happens entirely in your browser using FFmpeg compiled to WebAssembly. Your video file never leaves your device, ensuring complete privacy and security.
You can adjust video speed from 0.25x (quarter speed, extreme slow motion) to 4x (quadruple speed). Use preset buttons for common speeds or the slider for precise control.
Yes, the audio speed is adjusted to match the video speed. When you speed up a video, the audio pitch increases accordingly. When you slow it down, the pitch decreases. This maintains audio-video synchronization.
Processing time depends on your video length, resolution, and device performance. A 1-minute 1080p video typically takes 30-60 seconds. The first use requires downloading the video processor (~30 MB), which is cached for future use.
The maximum file size is 500 MB. Videos between 200-500 MB will process but may take several minutes depending on your device. For best performance, we recommend files under 200 MB.
Need to Convert or Compress Images?
Convert between HEIC, JPG, PNG, WebP, AVIF, and more, or compress images for the web.