diff --git a/sway/sway.5.txt b/sway/sway.5.txt
index fdf5c0c10..446995d5e 100644
--- a/sway/sway.5.txt
+++ b/sway/sway.5.txt
@@ -300,6 +300,10 @@ The default colors are:
 **output** <name> <position|pos> <X,Y>::
 	Configures the specified output to be arranged at the given position.
 
+**output** <name> <scale> <I>::
+	Configures the specified output to be scaled up by the specified integer
+	scaling factor (usually 2 for HiDPI screens).
+
 **output** <name> <background|bg> <file> <mode>::
 	Sets the wallpaper for the given output to the specified file, using the given
 	scaling mode (one of "stretch", "fill", "fit", "center", "tile").