Compress 4K Video Online
4K video files can be enormous — perfect for cinematography, impractical for sharing. Compress and optionally downscale your 4K footage right in your browser.
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Strategies for 4K compression
You have two options: (1) Keep 4K resolution but reduce bitrate via quality slider — good for archiving. (2) Downscale to 1080p for sharing — files are 4-8x smaller and look great on most screens.
How to Get Started
Key Features
4K capable
Handles 4K UHD (3840×2160) footage from cameras, drones, and phones.
Downscale option
Select 1080p from the resolution dropdown to shrink 4K files by 75%+.
Patience required
4K processing takes time in a browser. A 5-minute 4K clip may take 10–20 minutes.
Private and free
Your 4K footage never leaves your device. No cloud upload required.
Frequently Asked Questions
How much can I compress a 4K video?
Keeping 4K at 65% quality: ~60% reduction. Downscaling to 1080p: ~80-85% reduction. Downscaling to 720p: ~90%+ reduction.
Is it better to keep 4K or downscale to 1080p?
For sharing on social media or web, 1080p is indistinguishable from 4K on most screens. Keep 4K only for archiving or large display use.
My 4K video is 10GB — will this work?
Very large files may exceed browser memory limits. Try splitting the video first, or compress a shorter clip.
Does this work with 4K MOV from iPhone?
Yes. iPhone 4K MOV files are supported and usually process faster due to H.264 encoding.
Related
Ready to compress your 4K video?
Go to the Video Compressor →