Video · 2 min read
How to reduce video size
Video takes a lot of space because of high resolution, bitrate and duration. Here is what actually reduces the file size and what only hurts quality.
Updated: November 2, 2026
Why video files are so large
Video size depends on resolution, frame rate, bitrate, codec and duration. A 10-minute 4K clip can easily take several gigabytes, even when there is little motion in the frame.
What really reduces size
- Lower the resolution. 1080p is usually enough for websites and social media; 4K is not always necessary.
- Lower the bitrate. This is the main compression parameter, but too low a bitrate causes artefacts.
- Change the codec. H.264 is universal, H.265 and VP9 are more efficient but less widely supported.
- Shorten the clip. Trimming unnecessary footage is the most honest way to reduce the file.
- Remove extra tracks. Multiple audio tracks and subtitles add weight too.
Formats and tools
MP4 with H.264 is the universal option. WebM with VP9 is often smaller at similar quality but may not open on phones and TVs. GIF is not suitable for long videos: it is almost always heavier than video.
Our MP4 to WebM converter re-encodes the video on the server and is a quick way to reduce weight. For precise bitrate and resolution control, use a desktop editor or ffmpeg.
Limits
The service accepts video up to 100 MB, 5 minutes long and Full HD resolution. For larger files, prepare a smaller copy in advance.
Questions and answers
Which is smaller: MP4 or WebM?
At comparable quality, WebM with VP9 is often smaller than MP4. But WebM is not supported on every device, so keep MP4 for universal playback.
Does converting MP4 to GIF reduce size?
Usually not. GIF stores frames separately and is often larger than the video. To reduce size, transcode to WebM or lower the resolution.
What affects size more: resolution or bitrate?
Both matter. Dropping from 4K to 1080p with a sensible bitrate gives the biggest effect, but text and fine details may lose quality.
Can I compress video without quality loss?
Fully lossless only if you shorten the clip or use a more efficient codec without visible quality changes. Usually a small loss is unavoidable.