Dimensions for a standard crib used in the home, child care center or family child care home are 28 5/8 inches in width by 52 3/8 inches in length. In centimeters, this is 71 1.6 centimeters wide by 133 1.6 centimeters long.
Mattresses used in full-sized cribs are required to be 27 1/4 inches by 51 1/4 inches by no more than 6 inches thick. This requirement is designed to prevent head entrapment and suffocation. Crib standards are in place to prevent injuries or death to children from falls or entrapment due to parts failure. They cover required size dimensions, crib construction and mattress safety.