Show every screen resolution your Mac can use

Why it happens

Displays starts with a handful of friendly choices, from Larger Text to More Space, because most people only need those. The full list of exact resolutions is hidden until you ask for it. Showing it lets you pick a precise size, such as your external monitor's native resolution.

How to fix it

1. Open System Settings and click Displays. If you have more than one screen, click the one you want to change at the top.

   Displays

2. If the choices are a row of small screen pictures, click Advanced…, turn on Show resolutions as list and click Done.

   Displays›Advanced…

3. Turn on Show all resolutions. The full list of sizes appears.

   Displays›Resolution›Show all resolutions

4. Click the resolution you want. The screen changes straight away, and if you don't like it, pick another.

Still not fixed?

1. For an external monitor, pick its native resolution, often printed in its manual or on the box. That's the sharpest setting.

2. If the monitor's native resolution still isn't in the list, try a different cable, adapter or port. Some cables and adapters can't carry high resolutions.

3. Check the Refresh rate pop-up for that display. Some monitors offer different resolutions at different refresh rates, so try another rate.

   Displays›Refresh rate

4. If the right resolution never shows with a known good cable, or the picture is blurry at every setting, contact the monitor's maker, or Apple Support or a repair shop for your Mac's built-in display.