The Internet says that the Macbook Air's resolution is 2560×1600, and that its supported scaled resolutions are:
- 1680 by 1050
- 1440 by 900
- 1024 by 640
But which of those supported scaled resolutions is the effective resolution of the Macbook by default? Or maybe it's not even listed. If you use the non-default scaled resolutions, they don't look quite right to my eyes, and so I want to know how small or large everything is. Most software doesn't factor in hardware pixels when choosing what size to display.
For example, the Macbook Pro 16-inch has a native 3072×1920 resolution, and its supported scaled resolutions are:
- 2048 x 1280
- 1792 x 1120
- 1344 x 840
- 1152 x 720
#2 is the effective resolution when running in default retina mode, giving the Macbook Pro a PPI of 132.08
Best Answer
By default, Mac Retina displays are always at scaled to 2x the 'actual' resolution. So a 2560 x 1600 display will be a "Hi-res" version of 1280 x 800.
I suspect that Apple's list of "supported scaled resolutions" does not include the default 2x Retina setting. This is backed up by the wording used on my 15" MBP:
The Scaling options in System Preferences offer 5 options: four of them being the scaled sizes and the middle button being the default. (I'm hovering the mouse over the 2nd from left in the the image.)
The 16" MBP's default resolution is 1536 x 960 "Hi-res".
You are right that "most software doesn't factor in hardware pixels when choosing what size to display" - that's the job of the OS. MacOS's use of 2x scaling is designed to be the clearest.
If the non-default scaled resolutions don't look right to your eyes (understandably so), then just use the default.