Granite countertop thickness is a pretty straightforward affair, yet homeowners frequently ask us, “How thick should granite countertops be?”

This, like most things, is a matter of preference but there are some industry standards to help guide you.

So let’s go over standard granite countertop thickness.

You Have Two Standard Options For Granite Thickness

1) Two centimeter (2 cm) granite slabs were the previous industry standard. And while some still argue in their favor, 3 cm thickness has become the new standard for kitchen countertops and most other applications.

2 cm granite slabs went out of favor mostly because they involve extra work which equates more expenses for you, the homeowner. This is because they needs a plywood substrate, or support layer, when they are installed. This, and the fact that you often have to laminate an additional strip onto the front facing edges to create your countertop edging, are the main reasons they’ve fallen from grace.

a comparison of different granite thickness

Notice the extra piece that must be added to the 2cm. This creates an extra seam on your countertops.

2) Three centimeter (3 cm) countertops are the new king of the castle. Their 33% extra thickness means you do not need plywood under your granite countertops or extra lamination. Ultimately, they will be stronger and more refined.

3) Bonus: 6 cm thick granite countertops. For a truly eye-popping countertop many homeowners stack two slabs of 3 cm granite to create the Mastadon:

a quartzite 6 cm granite countertop

^ Photo Credit:


a 6cm thick granite countertop

a mastadon and a mammoth together

Obviously, if you choose to install the Mastadon then you will need to add plywood support on top of your cabinets and laminate the granite slabs together. Achieving this striking look can be well worth it, though.

A Word On Cabinets

Cabinets and granite countertops are like siblings: it’s better if they play nice together. Most people shop for their countertops after they have their cabinets chosen and installed.

It’s important to trust your cabinet-maker and installer because they need to be level when placing a slab of granite on top. While most variances can be overlooked, and the weight of the granite will actually help. There are some instances when the cabinets are so misaligned that the granite fabricator cannot install the countertops.

This is a headache for everyone.

Granite Countertop Overhang

The standard overhang of a kitchen island that you want to put stools under is 12 inches. The granite, marble or quartzite that you choose will further determine if an over hang of 12 inches will require corbels. A corbel is an L-shaped support that helps strengthen the countertop overhang.

a kitchen island with corbels

Some nice wrought iron corbels.

Your granite fabricator will be able to tell you if you need corbels for your desired countertop overhang.

The standard overhang of a countertop without seating is 1 to 1.5 inches from the cabinet bases. This overhang prevents spills and crumbs from making their way into your drawers, and it also feels more natural when you are standing at the countertop with your toes up to the base of the cabinets.

We hope this has helped clear up any doubts you had about granite thickness and how much overhang to have for your countertops.

Please call us if you have any other questions that we could answer for you.

For further information on buying granite countertops see our guide:

Colorado Countertops: Tips On How To Choose The Best