Standard countertop dimensions

Quick reference

Height

Kitchen counters are 36 inches from the floor to the top of the stone. Base cabinets are built to 34½ inches so that a 1½-inch top lands at 36. If your top is thinner, a plywood or shim layer can make up the difference. Bar counters are 42 inches, and some islands step up to bar height on the seating side.

Depth and overhang

Base cabinets are 24 inches deep without their doors. The counter overhangs the front by 1 to 1½ inches, so it is about 25 to 25½ inches deep, sometimes a little more where the back wall is out of line. Measure from the wall to the front of the cabinet doors and add your overhang.

Overhang for seating

The National Kitchen & Bath Association recommends 24 inches of counter width for each person, and knee space 15 inches deep at a 36-inch counter, 12 inches at a 42-inch bar, and 18 inches at a 30-inch table-height counter.

A long stone overhang needs support. Advice varies: Arizona Tile says 2 cm stone needs support beyond 6 inches of overhang and 3 cm beyond 10 inches, while MSI allows more for its quartz. Use brackets or corbels whenever you go past your fabricator’s limit, and never stand or sit on an unsupported overhang.

Thickness: 2 cm vs 3 cm

Stone countertops come in two common thicknesses. 2 cm is about ¾ inch and lighter; it is usually installed on a ¾-inch plywood sub-top, which also raises it to the usual height. 3 cm is about 1¼ inches, heavier and stiffer, and usually sits right on the cabinets. MSI gives about 9 to 10 pounds per square foot for 2 cm quartz and 13½ to 15 for 3 cm.

Bathroom vanities

Bathroom vanities run shallower and often lower than kitchen cabinets. Measure the cabinet you have rather than assuming a size; see bathroom vanity tops.