macOS: Take screenshots as JPG on macOS

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I take tons of screenshots on my Mac using the key combination cmd-shift-4 and after I switched from my old Apple Cinema Display which wasn’t retina to the new Studio Display which is 5K I noticed the size of some screenshots was HUGE.

macOS by default uses PNG as the format for screenshots, and depending on what it’s in the screenshot, you can have like 10MB screenshots very easily.

Run this command in the terminal:

defaults write com.apple.screencapture type jpg

followed by

killall SystemUIServer

This will make the screenshots use JPG for the format, which will be much more lightweight.

Lessons in this unit:

0: Introduction
1: How to use the macOS terminal
2: Productivity gains of using a Mac and an iOS device
3: A way to set up automations in macOS easily
4: How to hide a file or folder in macOS Finder
5: How to install a local SSL certificate in macOS
6: Reverting a file to a previous version, on a Mac
7: ▶︎ Take screenshots as JPG on macOS
8: Convert an image or resize it using macOS Shortcuts
9: Concatenating videos on macOS
10: Fix files creation date in macOS
11: Freeing space on a Mac
12: How to add an “Open in Terminal” icon in macOS Finder
13: How to add an “Open in VS Code” icon in macOS Finder
14: How to find the bundle ID of a Mac app
15: How to Fix the "Your CLT does not support macOS 11" error in macOS
16: How to play a sound from the macOS command line
17: How to remove the shadow from window screenshots in macOS
18: Removing all Homebrew stuff
19: Run a Node.js script from your macOS menu bar