Speed Up or Slow Down Video
Free online tool to speed up or slow down any video. Adjust playback from 0.25× (quarter speed slow-mo) to 4× (fast-forward / timelapse), audio pitches with the new speed. MP4, MOV, MKV, WebM all supported. Runs in your browser — no upload, no watermark, no sign-up. Faster than Clideo, Kapwing, or Online-Convert for short clips.
Drop files here or click to browse
Max 10240.0 MB per file · drop multiple for batch
or press Ctrl+V to paste
100% private — files never leave your device
·Free — no sign up, no watermark
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How to Use Speed Up or Slow Down Video
- Drop your video onto the speed changer (MP4, MOV, MKV, WebM all work)
- Set the speed: above 1.0 to speed up (2× = double speed), below 1.0 to slow down (0.5× = half speed)
- Preview to confirm the new pace, then click Process
- Download — full-quality MP4 with audio pitched to the new speed
Features
- Speed up video from 1.25× to 4× — perfect for TikTok / Reels speed-ups, timelapse, tutorial pace-up
- Slow down video from 0.75× to 0.25× — ¼-speed slow motion, replay analysis, cinematic moments
- Audio pitches with the new speed (the nightcore / chipmunk feel above 1×, deeper voice below 1×)
- Live preview before processing — confirm the new pace before saving
- Runs in your browser via FFmpeg WebAssembly — nothing uploads to a server
- MP4, MOV, MKV, WebM all supported; image-quality stays identical (only timing changes)
- Free with no watermark, no sign-up, no file size cap below plan limit
Frequently Asked Questions
- How do I speed up a video online?
- Drop the video into the speed changer, drag the speed slider above 1.0× (1.5× / 2× / 3× / 4× are popular speed-up values), click Process. Audio speeds up with the video and pitches higher. The whole thing runs in your browser via FFmpeg WebAssembly — no upload, finishes in seconds for short clips.
- How do I slow down a video online?
- Same tool — drag the speed slider BELOW 1.0× (0.75× / 0.5× / 0.25× for progressive slow-mo). The audio pitches lower with the slowdown. For AI-smooth slow motion that adds in-between frames (instead of just repeating frames), use our AI Slow Motion tool which uses AI frame interpolation.
- Does the audio sound weird when I change video speed?
- It pitches to match the new speed — the nightcore / chipmunk effect above 1×, deeper / slower voice below 1×. This is the natural FFmpeg behavior and matches how most video apps handle speed changes. For pitch-preserved speed (audio plays faster but voices stay normal), use a dedicated AI tool — not currently supported in this changer.
- How is this different from Clideo, Kapwing, or Online-Convert?
- Speed and privacy. Clideo / Kapwing / Online-Convert upload your video to their server, queue it, re-encode, send back — slow and your file briefly sits on their disk. This speed changer runs locally in your browser; nothing uploads, no queue, free with no watermark or sign-up cap.
- Can I make a timelapse with this tool?
- Yes — 4× speed compresses a 4-minute video into 1 minute, giving you a timelapse-style speedup. For extreme timelapse (16× / 32× / 64×), run the tool multiple times — 4× twice gives 16× total.
- What speed values work best for TikTok speed-ups?
- 1.5× is the most popular for TikTok / Reels — fast enough to feel snappy, slow enough that viewers can follow. 2× is great for tutorials. 3× / 4× are timelapse territory. For slow-motion clips, 0.5× is the standard.
- Will speed-changing reduce video quality?
- Minimally — the video is re-encoded at the new pace, but we use high-quality H.264 with a low CRF. The visual difference is imperceptible. The audio quality stays at the original bitrate.