Although it appears that upper cabinets mounted to the kitchen wall are the same height as base cabinets, they are indeed smaller. The standard height for these cabinets is 30 inches. This is the height for those cabinets hanging directly above counter space, for example. The depth of upper cabinets is 12 inches, but this measurement provides plenty for storage. In addition, the width measurement varies greatly, as cabinets may be built as single or double-door cabinets, ranging in size from 12 to 48 inches wide.
Smaller cabinets are located on top of range hoods, fridges and other tall appliances in the kitchen. These smaller cabinets are often double-door cabinets with a single shelf to store items. The height of these types of cabinets reaches a mere 15 inches commonly, so they fit right above taller appliances or range hoods. The general width is the same as the taller upper cabinets for consistency.
Upper cabinets are shorter in height than base cabinets, as base cabinets rest on the floor and provide support to the kitchen counter. Although they appear to be identical, base cabinets are 4 1/2 inches taller than the upper mounted cabinets, standing at 34 1/2 inches. A thick countertop may provide additional height to the base cabinets. In addition, some base cabinets may be raised using wooden blocks as the base to provide additional height.
Custom-made cabinets may not follow the standard height for upper kitchen cabinets, especially if the custom cabinets are made for smaller kitchens with limited wall space or slanted ceilings. Although upper cabinets have standard height measurement, it does not mean that kitchen cabinets must follow these measurements.