The size is listed as free size. It's estimated to be 26cm. These slippers are advertised to soften footsteps and minimize disturbance to those downstairs. However, since my house is a detached house, they were unnecessary. These are used items stored at home, so please understand this before purchasing. [Reprinted from the website where I purchased them] Slippers Cotton Linen encologi Room Shoes Open-toe Thick Sole House Slippers Washable Slippers Guest Use Quiet and Lightweight Indoor Slippers Non-slip Toilet Room Shoes Border Pattern Washable Indoor Slippers Summer Spring Easy to Wear House Slippers (Brown)