What are the differences between CDL classes A and B?

The distinction between CDL Class A and B is based on the size of the truck covered by each license type (A, B, C). A Class A license takes seven weeks to complete and includes 168 classroom hours. This is because CDL A covers the heaviest of trucks, such as flatbeds, semi-trucks, and tractor-trailer buses, with a gross combination weight rating (GVWR) of 26,001 or more pounds. On the other hand, a Class B license takes about four to eight weeks to complete and includes 70 to 120 classroom hours. The CDL B license covers trucks at moderate to heavy weights, including straight trucks, buses, garbage trucks, and delivery trucks.