Countertop Square Footage Calculator
Countertop area and slab count for a kitchen.
Enter your values
Enter the run 1 length in ft.
Enter the run 2 length in ft.
Enter the counter depth in in.
Enter the front overhang in in.
Enter the waste/seam allowance in %.
Enter the slab usable area in sq ft.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Countertop area
- 36 sq ft
- Area with waste/seams
- 43.2 sq ft
- Slabs needed
- 1
Quick answer
Countertop area is the sum of each run's length times depth including overhang, plus waste for seams and cuts.
area = sum(length x (depth + overhang)) x (1+waste%)
At a glance
| What it does | Countertop area and slab count for a kitchen. |
|---|---|
| Category | Home & DIY |
| Inputs needed | Run 1 length, Run 2 length, Counter depth, Front overhang, Waste/seam allowance, Slab usable area |
| Main output | Countertop area |
| Formula | area = sum(length x (depth + overhang)) x (1+waste%) |
| Cost | Free — no sign-up, no download |
How to use the Countertop Square Footage Calculator
- 1Add up the length of each counter run.
- 2Enter cabinet depth plus front overhang for the total counter depth.
- 3Add 15-25% waste for natural stone seams, veining match and cutouts.
Inputs explained
- Run 1 length(ft)
- Enter the run 1 length in ft.
- Run 2 length(ft)
- Enter the run 2 length in ft.
- Counter depth(in)
- Enter the counter depth in in.
- Front overhang(in)
- Enter the front overhang in in.
- Waste/seam allowance(%)
- Enter the waste/seam allowance in %.
- Slab usable area(sq ft)
- Enter the slab usable area in sq ft.
Worked example
Using the values the calculator loads with:
Inputs
- Run 1 length10 ft
- Run 2 length6 ft
- Counter depth25.5 in
- Front overhang1.5 in
- Waste/seam allowance20 %
- Slab usable area45 sq ft
Results
- Countertop area36 sq ft
- Area with waste/seams43.2 sq ft
- Slabs needed1
Frequently asked questions
Why is stone waste so high?
Slabs are irregular, sinks and cooktops cut out material, and pattern matching wastes more of the slab.
Laminate vs stone waste?
Laminate sheet goods generally need far less waste allowance than natural stone slabs.
What do I need to enter into the Countertop Square Footage Calculator?
Just 6 values: run 1 length, run 2 length, counter depth, front overhang, waste/seam allowance, slab usable area. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Countertop Square Footage Calculator work out the answer?
Countertop area is the sum of each run's length times depth including overhang, plus waste for seams and cuts. It applies the formula area = sum(length x (depth + overhang)) x (1+waste%) and shows the working so you can check each step by hand.
Is the Countertop Square Footage Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.