Countertop Square Footage Calculator
Section 1 (e.g. Main Counter)
Section 2 (e.g. Island or L-Shape)
Section 3 (e.g. Backsplash or Bar)
Additional Options
Measurement Results
Net Square Footage:
0.00 sq ft
Waste Allowance:
0.00 sq ft
Total Square Footage Needed:
0.00 sq ft
Estimated Material Cost:
$0.00
How to Calculate Countertop Square Footage
Whether you are installing granite, quartz, marble, or laminate, knowing your exact square footage is the first step in budgeting for a kitchen or bathroom remodel. Countertops are rarely a single simple rectangle, which is why we break the calculation down into sections.
The Basic Formula
To find the square footage of any rectangular section, use this formula:
(Length in Inches × Width in Inches) ÷ 144 = Square Footage
Since there are 144 square inches in a square foot (12″ x 12″), you must divide the total square inches by 144 to get the square footage required by fabricators.
Step-by-Step Measuring Guide
- Measure Length: Measure along the back wall where the countertop will sit. If you have an L-shaped kitchen, measure the long side first, then measure the remaining piece starting from the edge of the first piece.
- Measure Width: Standard base cabinets are 24 inches deep. With a standard 1.5-inch overhang, most kitchen countertops are 25.5 inches wide. Islands typically range from 36 to 48 inches wide.
- Include Backsplashes: If you are ordering matching stone backsplash, measure the length and height (usually 4 inches) and treat it as another section.
- The Waste Factor: Fabricators recommend adding 10% for "waste." This covers the material lost during cutting, seam matching, and potential breakage.
Example Calculation
Scenario: A kitchen has one main counter (120 inches long) and an island (60 inches long).
- Section 1: 120″ x 25.5″ = 3,060 sq in
- Section 2: 60″ x 36″ = 2,160 sq in
- Total Sq In: 5,220
- Total Sq Ft: 5,220 ÷ 144 = 36.25 sq ft
- With 10% Waste: 36.25 x 1.10 = 39.88 sq ft
Why Precision Matters
Underestimating your square footage can lead to significant project delays or higher costs if the fabricator has to source a second slab from a different batch, which may not match in color or grain. Always round up to the nearest inch when measuring to ensure you have enough material.