Patio Calculator
Planning a patio means choosing between pavers and poured concrete, then ordering the right amount of material. This calculator covers both options. For a paver patio, it calculates the total square footage, the number of pavers needed (accounting for joint width and a waste factor), and the cubic yards of sand required for the 1-inch setting bed. For a poured concrete patio, it calculates the cubic yards of concrete at a standard 4-inch slab thickness. Pavers are typically installed over a compacted gravel base (4 to 6 inches) topped with a 1-inch sand setting bed. The paver face size and joint width determine how many pavers fit in the area. Common paver sizes are 4x8 inches, 6x6 inches, and 12x12 inches. Standard joint width is 0.25 inches (1/4 inch), though dry-laid natural stone may use wider joints. Concrete patios skip the paver and sand steps but require forms, reinforcement (wire mesh or rebar), and curing time. Always check local building codes for slab thickness requirements if the patio will support a structure or vehicle traffic.
Patio material formulas
Area = Length (ft) x Width (ft)
Pavers per row = Floor(Length (in) / (Paver length + Joint))
Pavers per column = Floor(Width (in) / (Paver width + Joint))
Base pavers = Pavers per row x Pavers per column
Total pavers = Base pavers x (1 + Waste %)
Sand (cu yd) = Area (sq ft) x (1/12 ft) / 27
Concrete (cu yd) = Area (sq ft) x Slab thickness (ft) / 27
Worked example
Patio: 12 ft x 10 ft. Paver: 6x6 in, 0.25 in joint. Waste: 10%. Slab: 4 in.
- Area = 12 x 10 = 120 sq ft
- Pavers per row = Floor(144 / 6.25) = 23
- Pavers per col = Floor(120 / 6.25) = 19
- Base pavers = 23 x 19 = 437; with 10% waste = 481 pavers
- Sand = 120 x 0.0833 / 27 = 0.37 cu yd
- Concrete (4 in) = 120 x 0.333 / 27 = 1.48 cu yd
Frequently asked questions
How many pavers do I need for my patio?
Divide the total patio area in square inches by the area of one paver (including joint width) to get the paver count. Add 5 to 10 percent for cuts and breakage. This calculator handles that math for you.
How thick should the sand base be under pavers?
A 1-inch compacted sand setting bed is standard for most paver installations on a gravel base. The total base system (gravel plus sand) is typically 4 to 6 inches deep for a pedestrian patio. This calculator estimates the sand setting layer only.
How thick should a concrete patio slab be?
A residential concrete patio slab is typically 4 inches thick. Slabs that will support vehicles need at least 6 inches. This calculator uses 4 inches as the default thickness; you can adjust it.
What is the most common paver size?
Common concrete paver sizes include 4x8 inches, 6x6 inches, 6x9 inches, and 12x12 inches. Natural stone pavers vary more widely. Enter the actual paver face dimensions into this calculator for accurate results.
Should I add a waste factor for pavers?
Yes. Plan for at least 5 to 10 percent waste for cuts and breakage on a standard rectangular patio. For diagonal or herringbone patterns, add 10 to 15 percent. For complex shapes with many cuts, add up to 20 percent.
Sources
- Interlocking Concrete Pavement Institute (ICPI): Installation guidelines.
- Portland Cement Association: Concrete basics.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. Verify slab thickness requirements with your local building department.