How to Compress a Video

Videos can be enormous files. Compressing them makes them easier to send out to friends and family, share on social media, and save room on your phone. It's also simple to do.

Why Should You Compress Video?

Video compression is useful for a number of reasons. If you want your videos to upload and download quickly online, compression reduces the file size and makes that an easier process, especially on social media. If your video will only be watched on a device with limited storage, compression can help you save space. And if you want to send videos via email or over social networks, compression helps you meet any file size limits.

How Video Compression Works

The video you're shooting is probably compressed. Unless you're filming a video with a professional cinema camera, most video devices, whether they're your smartphone, your DSLR, or your camcorder, compress the video as you shoot it using a piece of software called a codec.

Codecs can be "lossy" or "lossless". For example, YouTube uses lossless codec H.264. The codec takes each frame of a video and divides it into a grid. It then compares the grids. If the information in the grid hasn't changed, those squares aren't loaded during playback in lossless formats, or discarded entirely with lossy formats.

Lossy codecs can squish a video down to a much smaller size, but it comes at a loss of quality. Lossless sacrifices space for quality, although it can achieve surprising reductions. As a general rule, modern devices shoot using a lossless codec and let you decide whether to compress it further when you're shooting and editing.

Before You Compress Video

With any video camera, there are certain steps you should take before you start filming.

1. Shoot in places with lots of light, particularly direct sunlight. The better lit your video is, the more information the codec has to work with. If possible, avoid shadows and subtle grades of dark colors.

2. Consider how your video will be seen. For example, if you're going to watch it on an older flatscreen, choose 1080p resolution.

3. If you know you're going to crush video files down to the smallest possible file size, shooting with a lossy codec beforehand saves time in rendering and reduces the risk of errors.

4. Use a simple editing program to cut your video down to only the most relevant parts. Even lossless codecs can pack shorter videos into much smaller spaces.

Compressing Video in Windows 11 and Windows 10

Windows 11 and 10 come with an app called Video Editor (formerly Movie Maker) that allows you to make simple videos. It's a useful way to quickly compress video in Windows. Another advantage is that it exports a copy of your project, instead of destroying your files, so you can go back and try again.

1. Assemble your video by uploading it to the app and putting any touches you want on it.

2. On Windows 11, select Finish Video in the upper-right corner. On Windows 10, select Export.

3. You're presented with a set of options: small, medium, and large (or low, medium, and high). Choose the one most appropriate to your needs.

Compressing Video in iOS and macOS

iMovie comes standard in both macOS and iOS. Starting with iOS, follow the next few steps.

1. Finalize your movie and tap the Export icon, which is in the center of the row.

2. Tap Save Video.

3. Choose a size from the menu.

The macOS version of iMovie works similarly to the iOS version, with a couple of differences.

1. after editing your movie, select the Share button in the upper-right corner of the iMovie screen.

2. Choose File as the export.

3. Select the size you'd like to export your video as. The smaller the number, the smaller the file size but the more the compression.

4. Your Mac saves the exported file wherever you tell it to, just like it does with every other file save.

Compressing Video in Android

While Android apps are not necessarily standardized, most modern Android devices include a simple video editing tool in the Gallery app with a few compression options.

1. Open the Gallery app and select a video.

2. Choose the edit function, usually the word Edit or a pencil icon.

3. Tap Resolution or Export and choose a resolution from the menu.

Compressing Video With a Website Video Editor

Websites that edit videos also offer compression options. However, they may compress the video as part of the export process. As a rule, once you're finished with your project, select a button marked Export Video or Finish Video and choose from a shortlist of options. Here, for example, are Clipchamp's choices.

Notice the stars next to higher-resolution options: These are paid features on this particular site. You may need to try out several sites to find one that allows better compression for free.