How to screenshot a selected area on Mac

Drag a rectangle on your Mac, lock an aspect ratio or type a pixel size, and take just that area.

An area capture is one rectangle. It is not a window, not the whole display, and not a marked-up image. You drag the region, then you stop.

Drag the rectangle

Click the Shoverlay menu bar icon or press your shortcut.
Choose Area.
Drag the rectangle. Hold to resize it before you confirm.
Lock an aspect ratio when the destination needs a fixed shape, or type a pixel size in the picker when the shot must be an exact width and height.

Screen Recording has to be allowed. If the picker does not appear, turn it on, quit Shoverlay, and open it again.

What you can do with the rectangle afterward

Quick Access sits on the capture. Copy or save is the end of this task. Annotation, pinning, and OCR are separate guides, so this shot stays a plain rectangle until you choose one of those.

Install Shoverlay on the Mac App Store.