I think it's about 24cm. I've included photos of the size, so please check them before purchasing. Outer Material: Rubber Closure Type: Lace-up About this item Foot Safety and Comfort: The rubber sole is truly comfortable with thick foam arch support inserts inside, flexible yet thick, preventing your feet from stepping on rocks and stones. Non-slip Outsole and Durability: Non-slip rubber sole, ergonomically molded shock absorption performance cushioning, and separate protective toe guard. Superior technology prevents the seams around the toes from fraying or tearing in a short time. Quick Drying with Drainage Holes: Unique, top-quality soles with 7 holes in each bottom allow water to flow out, creating a cooler and healthier shoe environment, and are extremely comfortable for quick drying during water sports. Excellent Elasticity and Standard Foot Model: Breathable and smooth fabric with fine stretch in the upper, flexible and comfortable. The smooth design of the neck prevents chafing when wearing our water shoes. Ergonomically molded standard foot model perfectly wraps your feet. Ultra-Lightweight Fashion: Like socks, ultra-lightweight and flexible, allowing you to wear them freely and comfortably. Perfect as an alternative to bulky water shoes. A pair of these shoes can make you more fashionable with individual character. ✔ Immediate purchase without comment is welcome★ ✔ The reason for stating "Like New" is because it has been opened once for photography. Please rest assured that the product itself is unused★ ✔ We ship from home storage and with simple packaging (may remove from the box or compress)★ ✔️ Please check the actual photos for the condition of the product★ 26-1