External displays on a Mac, fixed in plain English.
15 fixes for macOS 26 Tahoe and macOS 27 Golden Gate.
Your Mac isn't detecting your external monitorThe cable, adapter or port is not giving the Mac a signal, or macOS has not noticed the display yet.Use your MacBook with the lid closed on an external monitorThe MacBook needs power, a display and an input device before it stays awake with the lid closed.Make text sharp on your Mac's external monitorThe monitor is using a non-native or low-resolution mode, or is a low-pixel-density screen.Your external monitor is connected but stays blackThe monitor is detected but the mode or cable cannot carry the picture, or it is stuck after sleep.Connect a second monitor or TV to your MacPlug the monitor into a Thunderbolt/USB-C or HDMI port (with an adapter if needed); the Mac extends the desktop onto it.Your external monitor flickers or keeps blanking outA weak cable, adapter or the refresh rate setting is often the cause.Mirror or extend your Mac's screen on a monitor or projectorThe "Use as" setting decides whether a display extends your desktop or shows the same picture.Find out how many external displays your Mac supportsIt depends on the chip: base M1 and M2 laptops drive one external display, while newer and Pro or Max chips drive two or more.Fix an external monitor that's at the wrong resolution on your MacmacOS picked a lower resolution, or the cable or adapter cannot carry the full one.Arrange your displays so the mouse moves the right wayThe Arrange layout does not match how the monitors sit on your desk.Use an iPad, Apple TV or another Mac as a displayWireless and iPad displays are added from the Displays menu.Rotate your external monitor to portrait (or fix a sideways screen)The "Rotation" setting for the display does not match how it is physically placed.Make text bigger or smaller on your Mac's external monitorExternal monitors use a scaled resolution that sets text size.Your external monitor is stuck at 30Hz or 60Hz on your MacThe cable, adapter or port cannot carry the picture at a high refresh rate and resolution together.Why your M1 or M2 MacBook shows only one external monitorMacBooks with the base M1 or M2 chip support only one external display, no matter what hub you use.