Compress Video: Reduce MP4 File Size
Make a video small enough for email or messaging, compressed on your own device.
or drop it here
Accepts: MP4, MOV, WebM, MKV
Converted on this device. Your files are never uploaded.
File size is bitrate × length
A video's size is roughly its total bitrate (video plus audio) times its duration. At 5 Mbps, one minute is 5,000 × 60 ÷ 8 = 37,500 kB, about 37.5 MB; at 2 Mbps the same minute is 15 MB.
Compression lowers that bitrate. The presets set how far to go: Smaller file, Balanced or Better quality.
Lowering the resolution is the biggest lever
A 1080p frame has 1920 × 1080 ≈ 2.07 million pixels; 720p has 1280 × 720 ≈ 0.92 million, less than half. Fewer pixels need fewer bits for the same sharpness, so 720p with Balanced often looks better than a 1080p video squeezed hard.
The resolution setting is a maximum: a video that is already 720p isn't enlarged by a 1080p limit.
What compression can't do
Every pass is lossy, and fine detail, grain and fast motion degrade first. Compress from the original, not from a copy that was already compressed.
Results depend on the content: a mostly static screen recording shrinks far more than handheld footage with lots of movement.
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Questions
How small will my video get?
It depends on the footage and settings. The page shows the original and new size after compressing, so you can try another preset if it isn't small enough.
Which settings for watching on a phone?
Start with Balanced at 720p. If the result is still too large, choose Smaller file or 480p.
Can I compress a 4K video on my phone?
Maybe not. Everything runs in the device's memory, and long 4K videos can exceed what a phone browser allows. A computer handles them more reliably.
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