diff --git a/README.md b/README.md
index aeff2e5..93057e0 100644
--- a/README.md
+++ b/README.md
@@ -269,8 +269,36 @@ You can also pass optional parameters
   --status-quo            : Do not commit any changes to disk/snapshot.
   --fullscreen            : Starts VM in full screen mode (Ctl+Alt+f to exit)"
   --no-smb                : Do not expose the home directory via SMB.
+  --screen <screen>       : Use specified screen to determine the window size.
 ```
 
+<ins>Note about screen and window size</ins>
+
+`qemu` will always default to the primary monitor to display the VM's window.
+
+Without the `--screen` option, `quickemu` will look for the size of the smallest monitor, and use a size that fits on said monitor.
+
+The `--screen` option forces `quickemu` to use the size of the given monitor to compute the size of the window. **It wont't use that monitor to display the VM's window if it's not the primary monitor**. This is usefull if the primary monitor if not the smallest one, and if the VM's window doesn't need to be moved around.
+
+The `--screen` option is also usefull with the `--fullscreen` option, again because `qemu` will always use the primary monitor. In order for the fullscreen mode to work properly, the resolution of the VM's window must match the resolution of the screen.
+
+To know which screen to use, type :
+```
+xrandr --listmonitors | grep -v Monitors
+```
+The command will output something like this :
+```
+ 0: +*HDMI-0 2560/597x1440/336+1920+0  HDMI-0
+ 1: +DVI-D-0 1920/527x1080/296+0+0  DVI-D-0
+```
+The first number is what needs to be passed to the `--screen` option.
+
+For example : 
+```
+quickemu --vm vm.conf --screen 0
+```
+will use my big screen to compute the size of the window, and make it 2048x1152. Without the `--screen` option, it would have used the smallest monitor and make the window 1664x936.
+
 ## TODO
 
   - [ ] SPICE support
diff --git a/quickemu b/quickemu
index e777b24..67cc235 100755
--- a/quickemu
+++ b/quickemu
@@ -319,10 +319,19 @@ function vm_boot() {
   local Y_RES=648
   if [ "${XDG_SESSION_TYPE}" == "x11" ]; then
     local LOWEST_WIDTH=""
-    LOWEST_WIDTH=$(xrandr --listmonitors | grep -v Monitors | cut -d' ' -f4 | cut -d'/' -f1 | sort | head -n1)
+    if [ -z "${SCREEN}" ]; then
+      LOWEST_WIDTH=$(xrandr --listmonitors | grep -v Monitors | cut -d' ' -f4 | cut -d'/' -f1 | sort | head -n1)
+    else
+      LOWEST_WIDTH=$(xrandr --listmonitors | grep -v Monitors | grep "^ ${SCREEN}:" | cut -d' ' -f4 | cut -d'/' -f1 | head -n1)
+    fi
     if [ "${FULLSCREEN}" ]; then
-      X_RES=$(xrandr --listmonitors | grep -v Monitors | cut -d' ' -f4 | cut -d'/' -f1 | sort | head -n1)
-      Y_RES=$(xrandr --listmonitors | grep -v Monitors | cut -d' ' -f4 | cut -d'/' -f2 | cut -d'x' -f2 | sort | head -n1)
+      if [ -z "${SCREEN}" ]; then
+        X_RES=$(xrandr --listmonitors | grep -v Monitors | cut -d' ' -f4 | cut -d'/' -f1 | sort | head -n1)
+        Y_RES=$(xrandr --listmonitors | grep -v Monitors | cut -d' ' -f4 | cut -d'/' -f2 | cut -d'x' -f2 | sort | head -n1)
+      else
+        X_RES=$(xrandr --listmonitors | grep -v Monitors | grep "^ ${SCREEN}:" | cut -d' ' -f4 | cut -d'/' -f1 | head -n1)
+        Y_RES=$(xrandr --listmonitors | grep -v Monitors | grep "^ ${SCREEN}:" | cut -d' ' -f4 | cut -d'/' -f2 | cut -d'x' -f2 | head -n1)
+      fi
     elif [ "${LOWEST_WIDTH}" -ge 3840 ]; then
       X_RES=3200
       Y_RES=1800
@@ -555,6 +564,7 @@ STATUS_QUO=""
 USB_PASSTHROUGH=""
 VM=""
 SHORTCUT=0
+SCREEN=""
 
 readonly LAUNCHER=$(basename "${0}")
 readonly DISK_MIN_SIZE=$((197632 * 8))
@@ -607,6 +617,10 @@ else
             VM="${2}"
             shift
             shift;;
+          -screen|--screen)
+            SCREEN="${2}"
+            shift
+            shift;;
           -shortcut|--shortcut)
             SHORTCUT=1
             shift;;