The worktop thickness and depth.
Normal height for kitchen cabinets. The reason for this is that 18 inches of clearance between base cabinets and uppers are regarded as the optimal working space and with base cabinets generally 36 inches high with countertop included and 24 inches deep upper cabinets beginning at 54 inches provides the desired 18 inch clearance. Where the cabinets run all the way to the ceiling 48 inch cabinets are the logical choice. Common wall cabinet heights are 12 36 and 42 inches.
Although 18 inches is a typical minimum height kitchen cabinets can start much higher than this. In standard kitchens the wall cabinets are typically 30 or 36 inches tall with the space above enclosed by soffits. The trade off is that for every inch you raise the cabinets you will have more open space to work in but less storage space at an easily reachable height.