Countertops range in thickness. The standard thickness is 1 1/4-inch. This is a complete thickness and doesn't represent the thickness of the finish of the countertop. Usually countertops are placed over substrate materials such as plywood, medium density fiberboard, cement board or other materials. What a person sees and uses as the surface of the counter is often just a veneer or surface covering. The bulk of the countertop is below the surface.
The most common countertop is still the vinyl or laminate countertop. This countertop is durable and inexpensive. The substrate of a laminate countertop may be plywood, medium density fiberboard or some other composite material. The countertop surface is laminated to the substrate to produce the finish that the homeowner uses. Often the completed countertop is 1 1/4 inches thick.
Stone tile countertops are less expensive than solid stone counters. The tile is real stone but can range from 3/8 to 1/2 inch in thickness. The tile is mortared over a cement board or membrane covered plywood adding an additional 7/8 to 1 1/8 inch. This brings the thickness of the countertop to 1 1/4 to 1 1/2 inch. This counter can be a good choice for an upgraded countertop, as long as the edges are finished with a professional attention to detail.
The larger the sheet of stone that is used in a kitchen, the thicker the stone must be to hold up to the pressure of gravity. Usually a solid stone countertop will be up to 1 1/2 inches thick without any substrate material. This is a very heavy counter and the cabinets need to be well constructed to hold the weight of the counter. Smaller runs such as short bathroom vanity counters can be solid yet as thin as 1/2 inch thick. There is less stress on the smaller pieces of stone. The edges of thin counters are often built up to create the illusion of a thicker piece of stone.
Concrete, Stainless, Solid Surface
Concrete countertops and other sustainable composite countertops may be thicker than other countertops as they deal with similar size and pressure issues that are common with solid stone counters. Stainless steel requires less of a substrate and the edge is often exaggerated to create the appearance of a thick counter. Under the steel the counter substrate may be 3/4 inch plywood. Solid surface materials range from 1/4 to 3/4 inch veneer over medium density fiberboard. This type of counter will usually finish within the 1 1/4 inch standard thickness.