The short version
Trim the parts you do not need, lower the resolution one step, then lower the quality a notch, and check the result before you send it. Resolution is the biggest saving for the least visible damage. Keep your original file, because every time you compress a copy of a copy, the picture gets a little worse.
Why video files get so big
A video is a long run of pictures plus sound. Phone footage is recorded with generous settings so that it looks good and can be edited, which often means several hundred megabytes for every minute of 4K video. A typical 1080p file at around 8 megabits per second works out at roughly 60 MB a minute, because 8 megabits per second is 1 megabyte every second.
That is far too big for most email accounts, which commonly cap attachments at around 20 to 25 MB, and it is slow to upload from a phone on a weak connection. Compression solves this by throwing away detail that your eyes are unlikely to miss.
The three dials
Resolution is how many pixels are in each frame. 1080p has about 2.1 million pixels, 720p has about 0.9 million, and 4K has about 8.3 million. Dropping from 1080p to 720p means roughly 56% fewer pixels to store, and on a phone screen the difference is often hard to see.
Bitrate is how much data is spent on each second of playback. A lower bitrate means more visible blockiness and smearing in fast movement, in dark scenes and around fine detail. It is the "quality" setting in most tools.
Frame rate is how many pictures per second. Going from 60 to 30 frames per second removes half the frames, which helps, though it makes fast motion look less smooth. For talking, screen recordings and most social clips, 30 is plenty.
Resolution and bitrate are separate settings. A video can be small and sharp (low resolution with a decent bitrate) or large and soft (high resolution with a starved bitrate). The best result usually comes from lowering resolution first, so the remaining bitrate is spread across fewer pixels.
What to choose for where it is going
| Where it is going | Suggested resolution | Notes |
|---|---|---|
| Email or a chat message | 480p or 720p | Keep it short. Aim to land under the attachment limit, and trim first. |
| Social media post | 720p or 1080p | Most platforms re-compress what you upload, so a clean 1080p file beats a heavily squashed one. |
| Short loop on a website | 720p or lower | Small files load faster, and a looping clip rarely needs more. |
| Archive or later editing | Keep the original | Do not compress your only copy. |
These are starting points rather than rules. If the text in a screen recording looks fuzzy after compression, go back up a step in resolution, because small text is the first thing to suffer.
Trim first, then compress
The easiest way to make a video smaller is to make it shorter. Cutting a slow start, a long ending or a mistake in the middle shrinks the file in proportion, with no loss of quality at all. The Video Compressor lets you compress just a selected part of a clip, so you can trim and shrink in one step instead of editing the video somewhere else first.
Using the Video Compressor
Drop in an MP4, WebM or MOV file and pick a maximum resolution (keep the original, or cap it at 1080p, 720p or 480p). Choose a quality of high, medium or low, where low gives the smallest file. Then press Compress. There are two engines. Standard works on any device but takes roughly as long as the video itself. Fast mode processes the file directly instead of playing it back, so it is usually quicker on longer videos.
Everything happens in your browser. Your video is not uploaded, so the speed depends on your computer, and it is best to leave the tab open until the download button appears.
Mistakes that make videos look worse
- Compressing the same file again and again. Each pass loses a little more. Always start from the original.
- Scaling up. Making a 480p clip "1080p" adds file size but no detail.
- Choosing the smallest quality for everything. Low quality is fine for a quick preview and poor for anything with fast motion or dark scenes.
- Not watching the result. Play the compressed file all the way through, with sound, before you delete or send anything.
Try it yourself
Last updated 2 November 2026. These guides are general information written by the Cwtch.es team. Settings and platform limits change, so check the current details for any service you rely on.