How to compress a screen recording

Tutorials, demos and bug reports are usually screen recordings, and they often have to fit under an upload limit. The good news is that this kind of video is the easiest to make small, if you know where the savings are.

In short

Why screen recordings are easy to shrink

Video compression mostly stores what changed since the previous frame. On a desktop where only a cursor or a few lines of text change, almost nothing is new in each frame, so very little data is needed. Footage from a camera, with moving leaves, water and shaky hands, changes everywhere and needs far more.

In our own test, a mostly still 1080p60 test clip of 40 seconds started at only 4.8 MB, and the compressor could make it smaller still without any visible damage.

A quick recipe

  • Trim the start and end. Cutting the time you spend opening and closing the recording is free quality.
  • Lower the frame rate to 30 fps. A cursor and typing look the same at 30 fps, and each frame gets twice the data.
  • Use 720p for slides, tutorials and bug reports. Use the largest resolution option under More options if you want to force it.
  • Tick Remove sound if the recording is silent anyway. That space goes to the picture.

Fewer pixels, more bits for each pixel

At the same bitrate, 720p gives each pixel about 2.3 times as many bits as 1080p, and 480p about 5 times as many. That is why stepping down a resolution often looks cleaner than starving a large picture.

Keep the text readable

Text is the first thing to suffer. Small interface text can turn to mush at 480p, so for anything with fine print, stay at 720p or higher. If you need to go smaller, crop the recording to the window you are demonstrating instead of shrinking the whole screen, because a smaller area keeps its detail.

  • Increase the font size or browser zoom before you record.
  • Record only the window that matters, not the whole display.
  • Pause on important text for a second or two so people can read it.
Technical details

How the compressor decides

If the recording already fits the size you chose, the compressor keeps its resolution and frame rate and does not spend more bits than the original has. Only when the size budget is too small does it step down the resolution and then the frame rate, using bits per pixel as the guide. Because a still screen needs few bits per pixel to look clean, it often keeps a higher resolution than camera footage of the same size.

Bits per pixel: will the picture look clean?

bits per pixel, per frame. The same 2.5 Mbps goes a long way further at 720p and 30 fps. The thresholds (0.05 and 0.08) are rules of thumb, and the compressor uses them to warn you before you start.

Check what is on the screen first

Recordings often capture things you did not mean to share: notifications, other browser tabs, email addresses, file names. Look through the recording before you send it. Compressing on your own computer, as this tool does, keeps the recording off other people’s servers while you do.