Unit Definition (square inch) The square inch is a traditional unit of area. 1 in2 equals exactly 6.4516 cm2 or 645.16 mm2.
Unit Definition (square mile) The square mile is a traditional unit of area. One square mile is equal to 640 acres, 3 097 600 square yards, 258.9988 hectares, or 2.589 988 square kilometers.
