The surface area to volume ratio of an object is the relationship between two measurements. It is the ratio of Surface area to volume. It shows the comparison between the size of the outside of an object and the amount inside. Small or thin objects have a large surface area compared to the volume. This gives them a large ratio of surface to volume. Larger objects have small surface area compared to the volume so they have a small surface area to volume ratio. A large lump, for example, has a small ratio, and may be smashed into powder to give it a large surface to volume ratio.