How to Use This Concrete Patio Cost Calculator
Enter your patio's length and width in feet, then set the slab thickness, gravel base depth and waste allowance with the sliders. Pick who is doing the work, the surface finish and the reinforcement, and open “Adjust unit prices” to replace the default prices with numbers from your local ready-mix supplier and lumber yard. Press Calculate to see the total, the cost per square foot, the cubic yards to order, a line-by-line breakdown, and side-by-side comparisons of different thicknesses and finishes.
Why This Matters
A concrete patio is one of the best-value upgrades for a yard, and one of the easiest projects to misprice. Quotes for the same 12×12 slab can differ by a factor of two depending on the finish, whether an old patio must be broken out and hauled away, and whether the ready-mix truck charges a short-load fee. Small slabs suffer most. Under about 4 cubic yards, many plants add $75–$150, so a 12×12 patio costs more per square foot than a 20×20 one.
A homeowner comparing bids needs a baseline to judge whether $2,400 for 144 square feet is fair (it is above the usual range for a plain finish). A DIYer needs to know whether bagged concrete makes sense: a 12×12×4 in slab with 10% waste takes about 88 bags of 80-lb mix, which is roughly 3.5 tons to mix by hand. Landscapers, landlords budgeting for a rental and anyone planning a grill station, hot-tub pad or seating area can use the same estimate to set a budget before collecting quotes.
How It's Calculated
The calculator builds the price from the ground up and rounds quantities up, never down, so you are less likely to come up short:
Finish upgrades, demolition and labor are priced per square foot, with DIY rates covering materials and rentals only. The thickness and finish comparison tables re-run the same math with one setting changed. Sizing follows common residential rules of thumb: IRC R506 (concrete floors on ground, 3.5 in minimum) and ACI 332 residential guidance. Control joints are suggested at no more than 2 × the slab thickness in feet, the conservative end of the usual 2–3× rule. Local codes, frost depth and soil conditions vary. This is a budgeting estimate and not engineering, permit or inspection approval.
Worked Example
A 12 ft × 12 ft patio, 4 in thick, on a 4 in gravel base, with wire mesh, a broom finish, 10% waste, professional installation and the default prices:
- Area and perimeter: 12 × 12 = 144 sq ft; perimeter 48 ft.
- Concrete: 144 × (4 ÷ 12) = 48 cu ft; × 1.10 = 52.8 cu ft = 1.956 yd³, so order 2.00 yd³ × $165 = $330.00. Under 4 yd³, so add the $125.00 short-load fee.
- Gravel: 48 cu ft = 1.778 yd³ × 1.15 = 2.044, rounded up to 2.25 yd³ × $50 = $112.50.
- Mesh: 144 × 1.10 = 159 sq ft × $0.40 = $63.60.
- Forms and supplies: 48 × $2.50 + 144 × $0.25 = $156.00.
- Labor: 144 × $4.50 = $648.00.
- Totals: subtotal $1,435.10; plus 15% overhead and profit ($215.27) = $1,650.37; plus 10% contingency ($165.04) = $1,815.40, or about $12.61 per sq ft.
Switch to DIY with a ready-mix truck and the same patio drops to roughly $866, because labor, markup and the finish premium disappear.
Tips & Common Mistakes
- Don't skimp on the base. In clay or freeze-thaw soils, a compacted 4 in gravel base is commonly recommended for drainage, and it costs little compared with replacing a heaved slab.
- Order a little extra. Uneven subgrade eats concrete, and running short mid-pour creates cold joints. A 5–10% overage is cheap insurance.
- Plan for drainage. Slope the slab about ¼ in per foot away from the house, and call 811 before you dig.
- Cut control joints on time. Make them about one-quarter of the slab depth, spaced no farther apart than the figure shown in your results, within 6–18 hours of finishing.
- Compare quotes line by line. Check whether bids include demolition, grading, pump truck, sealer and permit fees. Odd shapes are best split into rectangles, estimated one at a time and added together.
Frequently Asked Questions
How much does a concrete patio cost per square foot?
A plain broom-finish patio typically runs about $8–$15 per square foot installed, and $4–$7 for DIY with a ready-mix truck. Stamped or colored finishes, demolition and small project sizes push the number higher.
How thick should a concrete patio be?
Four inches is the common standard for foot traffic, and residential codes such as IRC R506 set 3.5 inches as the floor for slabs on ground. Use 5–6 inches under vehicles, heavy planters, or hot tubs, and ask an engineer or your building department about concentrated loads.
How many yards of concrete do I need for a 12x12 patio?
At 4 inches thick, a 12×12 patio needs 1.78 cubic yards before waste. With 10% overage, plan to order about 2 cubic yards, which is what this calculator rounds to.
Is it cheaper to pour a patio myself?
Usually yes, by 50% or more, since labor is the largest line item. But finishing concrete is time-sensitive physical work, so for anything over about 2 cubic yards, use a ready-mix truck and recruit helpers rather than mixing bags.
Do I need a permit for a concrete patio?
It depends on your jurisdiction. Many places exempt small ground-level slabs, but size limits, setbacks, drainage rules, and HOA approval can still apply, and covered or attached patios often need permits. Call your local building department before you pour.
Does a patio need rebar or wire mesh?
Reinforcement does not prevent cracks, but it holds cracked sections together and helps with heavier loads. Many contractors use mesh or a #3 rebar grid at 18 inches on center in poor soils, climates with hard freezes, or when the slab will carry vehicles.