A variable size marker or sizer for garment hangers is disclosed. A gear-shaped wheel with cogs has various size indicia on each cog, and is inserted into a hanger to display the correct size indicia. The hanger has tabs to retain the sizer in place by mating with slits in the sizer. For example, if a displayed garment is size ‘large’, the user chooses the cog with “L” facing upwardly, and inserts the sizer into the hanger through the bottom of the hanger until the hanger's tabs click into the sizer's slits corresponding with the “L”. The “L” is then visible at the top of the hanger. The hanger is made of resilient material to flex outwardly to allow the sizer to be inserted and removed, yet hold the sizer in place when the hanger is in use.