How to Compress a Video Without Losing Much Quality
To compress a video, lower its resolution, lower its bitrate, or both. The fastest route is the MP4 compressor in your browser: load the video, choose a quality or a target file size, and download the smaller version. This guide covers what actually makes a video small, how to do it on Windows, Mac, iPhone and Android, and why a compressed file sometimes comes out bigger.
What makes a video file big
A video's size is roughly its bitrate multiplied by its length. The bitrate is how much data the file spends on each second of video. Four things push it up:
- Resolution. 4K has four times the pixels of 1080p.
- Frame rate. 60 frames per second has twice the frames of 30.
- Quality settings. A higher bitrate keeps more detail and costs more space.
- Length. More seconds means more data.
Every method below works by changing one of these. See what is video bitrate for the math.
The ways to make a video smaller
| Method | How much it helps | Cost |
|---|---|---|
| Lower the resolution | Large, especially from 4K to 1080p | Less detail, fine on a phone screen |
| Lower the bitrate or quality | Large, and you control it | Visible blocks if you push it too far |
| Trim the video | Proportional to what you cut | None, if you only remove what you don't need |
| Drop the frame rate | Moderate, for example 60 fps to 30 fps | Motion looks less smooth |
| Remove the audio | Small, audio is a minor part of the size | No sound |
| Use a more efficient codec | Smaller at the same quality | Older devices may not play it |
In your browser
- Open the MP4 compressor.
- Drop in your video.
- Choose how to shrink it: by quality, or by a target file size if you need to fit a limit.
- Check the preview, then download the result.
Two related tools cover common cases. The Discord video compressor aims at Discord's upload limit, and the video resizer lowers the resolution, for example from 4K to 1080p or 720p.
The work runs on your device, so the video never leaves it.
On Windows 11
Clipchamp is included with Windows 11. Import the video, drag it to the timeline and choose Export. Clipchamp offers 480p, 720p, 1080p and 4K, and Microsoft describes 480p as the smallest and 720p as a good fit for social media. Pick the lowest option that still looks fine.
On a Mac
In QuickTime Player, open the video, choose File, then Export As, and pick a lower resolution such as 1080p, 720p or 480p. For 4K and 1080p exports there is also a choice between Smaller File Size (HEVC) and Greater Compatibility (H.264). Smaller File Size is smaller, but not every device plays HEVC.
On iPhone
- Before recording: go to Settings, Camera, Record Video and choose a lower resolution or frame rate, such as 1080p HD at 30 fps instead of 4K at 60 fps.
- After recording: open the browser compressor in Safari and pick the video from your library.
On Android
Android camera apps let you choose the video resolution and frame rate before you record, usually in the camera settings. For a video you already have, open the browser compressor in Chrome.
Step by step: shrink a video to fit a limit
- Find the limit. For example, many email services cap a message at 25 MB. See how to email a large video.
- Trim anything you don't need. See how to trim a video.
- Use a target size just under the limit to leave room for audio and packaging.
- If the result looks too soft, lower the resolution instead of the quality, or shorten the clip.
Common problems
- The compressed file is bigger than the original. This happens when a tool exports at a higher resolution or bitrate than the source used. Microsoft notes the same for Clipchamp: exporting at a resolution above the original's can make the file larger. Pick an output at or below the source.
- The video looks blocky. The bitrate is too low for the amount of motion. Raise the quality, or lower the resolution so the same bitrate spreads over fewer pixels.
- The video won't play after compressing. It may be HEVC on a device without HEVC support. Compress to H.264 MP4, as explained in H.264 vs H.265.
- I compressed it twice and it looks worse. Each re-encode loses a little. Compress once, from the original.
Everything stays on your device
Compression runs in your browser, so your video is never uploaded.