The topper is 5 inches but only 1/2 inch of memory foam. The description and title of the item are a bit misleading. The only part of this topper that is memory foam is the 1/2 inch thick egg crate on top. The rest is just regular foam. Don't get me wrong... it is still comfortable, just left a bad taste in my mouth because I thought I was getting one thing... and found another in the box!