How to Set Up Multiple Monitors on Linux
From the graphical interface or with xrandr, and the difference between X11 and Wayland.
With the graphical interface
Settings → Displays — automatically detects connected monitors, letting you choose relative position (one to the left of the other, for example), individual resolution, and whether you want to mirror or extend the desktop across both.
From the terminal (xrandr, for X11)
xrandr --output HDMI-1 --right-of eDP-1 --auto
Places the HDMI-1 monitor to the right of the laptop's screen (eDP-1), with its automatic resolution.
X11 vs Wayland: if your system uses Wayland
(increasingly common), xrandr doesn't work the same way —
use wlr-randr as an equivalent, or simply the graphical
interface, which works in both cases without you having to worry
about which one you're using.
Tip: if a monitor shows up with the wrong resolution or position after connecting, try "Detect displays" from the graphical settings first before resorting to manual commands.
Frequently asked questions
Do I need to use the terminal to set up multiple monitors?
No, the graphical Settings → Displays interface covers most needs, including relative position and resolution for each monitor.
Why doesn't xrandr work on my system?
If you use Wayland instead of X11 (increasingly common on recent distributions), xrandr isn't compatible — use wlr-randr as an alternative, or the graphical interface, which works in both cases.