Which door hanger size should I choose?

For most campaigns, 4.25" x 11" is the sweet spot. If you need more room for a menu, map, photos or a tear-off coupon, go with 4.25" x 14". For bigger runs on a budget, the slimmer 3.5" x 11" or 3.5" x 8.5" work well. And 4" x 7" is just right for hotel signs and short notices.