How do I adjust the aspect ratio on my Mac's screen?

Changing your Mac's screen aspect ratio is simple. The aspect ratio and resolution of your Mac's display are adjusted using the Display preferences inside Settings. 

The options available depend on which Mac you are using, and will typically be set to the Default for that display.

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How to change aspect ratio on Mac screen

Here is how to change your aspect ratio on a Mac screen:

  1. Open System Preferences
  2. Click Displays. You should see the option "Default for Display" selected. This is the highest resolution for your current monitor
  3. Click Scaled

What you now see depends on whether you are using a Mac with Retina Display or a non-Retina Display Mac (or Mac with external display).

How to change aspect ratio on Mac screen: Retina Display Mac

If you have a Mac with a Retina Display you will see four windows marked "Larger Text" or "More Space". Clicking these enables you to adjust the size of items as they appear on your display, while your actual resolution remains at the Retina Display level.

There is no stock way to adjust the resolution of a Retina Display Mac. According to Apple: "Retina displays use scaled resolutions rather than the specific resolution settings that external displays use. If you need to use a different resolution than those available on the built-in display, attach an external display via HDMI, Thunderbolt or DisplayPort."

How to change aspect ratio on Mac screen: Non-Retina Mac and external display

How to change aspect ratio on Mac screen

If you're using a Mac with a non-Retina Display, or have attached an external display to your Mac, then you will get more options for adjusting the aspect ration on your Mac.

Click Scaled and you will see what options are available. The options you get largely depend on the screen you are using. On a MacBook Air with an 11-inch display you get the following options:

  • 1366 x 768
  • 1280 x 720
  • 1152 x 648

You can view more resolution options by holding down the Option key and clicking Scaled. On our test MacBook Air you then see a range of aspect ratios from 1366 x 768 all the way down to 800 x 600.

Some of these aspect ratios will not fit properly on the display. In that case you may see borders on the left and right of your screen. If you pick a resolution that is particularly small, you may also have problems fitting app windows on the screen. Apps with larger windows, such as iTunes, may wander off the left and bottom of the display.

In these instances you'll get a warning when you open the app. Return to Display Preferences and pick a different aspect ratio to be able to use the app properly.

How to change aspect ratio on Mac screen: Adjust aspect ratio warning

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