The biggest difference between bath towels and beach towels is size. Beach towels are generally much longer than bath towels. They're meant for lying on the beach, and the extra length gives a bigger space for a person to lie on. Bath towels range from 27 inches by 52 inches to 30 inches by 58 inches in dimension. However, beach towels are about a foot longer at around 30 inches by 70 inches, and some oversized beach towels are even larger.