Concrete Slab Cost Calculator
Quick answer: A 20 × 20 foot (400 square foot) slab typically costs about $2,300 to $4,000 at 4 inches thick with a gravel base, and $3,100 to $5,200 at 6 inches with reinforcement.
Estimate concrete slab cost for a patio, shed or garage pad. Pick 4 in, 6 in reinforced or stamped concrete for a low, typical and high installed price per sq ft.
Estimated total
- Low
- $2,300
- Typical
- $3,100
- High
- $4,000
$7.75 per sq ft all-in (range $5.75–$10.00)
Where the money goes (typical)
- Materials
- $1,420 (46%)
- Labor
- $1,680 (54%)
Line items (typical)
| 4 in, broom finish | $2,600 |
| 4 in compacted gravel base | $500 |
Patios, walkways and shed floors.
General U.S. estimates for installed cost, not quotes. We compared them with HomeGuide's thickness table (about $6–$8 per sq ft for 4 in and $8–$10 for 6 in) and Angi's stamped concrete range. Prices reviewed November 2026. Get at least three local quotes before you commit.
Concrete contractors quote slabs per square foot. The price covers forming, the ready-mix concrete, reinforcement, placing and finishing. Thickness and finish are the main drivers, and site prep such as excavation, a gravel base and removing an old slab can add a lot.
Enter the slab size and choose the thickness or finish. The estimator gives you the low, typical and high installed cost with the labor share. To work out the cubic yards to order, use the concrete calculator.
How the concrete slab cost estimate works
- Enter the slab area in square feet.
- Multiply it by the installed price per sq ft for the material you chose.
- Adjust for truck access and your local cost level.
- Add the extras you ticked, such as removal, and any permit fee.
- Show the result as a low, typical and high total, split into materials, labor and fees.
Multiply length × width in feet. A 10 × 10 ft pad is 100 sq ft, a two-car garage about 400 to 576 sq ft. At 4 inches thick, every 100 sq ft takes about 1.23 cubic yards of concrete.
Concrete Slab Cost by material
| Material | Installed per sq ft | Labor share | Notes |
|---|---|---|---|
| 4 in, broom finish | $5.00–$8.00 | 55% | Patios, walkways and shed floors. |
| 6 in, reinforced | $7.00–$11.00 | 50% | Driveways, garage floors and hot tub pads, with rebar or mesh. |
| Stamped or colored, 4 in | $10.00–$19.00 | 65% | Patterned to look like stone, brick or wood. Needs resealing every few years. |
Concrete Slab Cost by size
Typical total with the low–high range below it. Assumes truck can chute directly to the forms; average u.s.; 4 in compacted gravel base.
| Slab area | 4 in, broom finish | 6 in, reinforced | Stamped or colored, 4 in |
|---|---|---|---|
| 100 sq ft | $800$600–$1,000 | $1,050$800–$1,300 | $1,550$1,100–$2,100 |
| 200 sq ft | $1,550$1,150–$2,000 | $2,050$1,550–$2,600 | $3,050$2,150–$4,200 |
| 400 sq ft | $3,100$2,300–$4,000 | $4,100$3,100–$5,200 | $6,100$4,300–$8,400 |
| 600 sq ft | $4,650$3,450–$6,000 | $6,150$4,650–$7,800 | $9,150$6,450–$12,600 |
| 1,000 sq ft | $7,750$5,750–$10,000 | $10,250$7,750–$13,000 | $15,250$10,750–$21,000 |
What affects concrete slab cost
- Thickness and reinforcement. A 6 inch slab uses 50% more concrete than a 4 inch slab, and rebar or wire mesh adds material and labor.
- Decorative finish. Stamping, coloring and exposed aggregate roughly double the price of a plain broom finish.
- Site prep. Excavation, compacted gravel base and removal of an old slab can add $1 to $8 per square foot together.
- Access. If the truck can't reach the forms, the crew needs a pump truck or wheelbarrows, which adds cost.
- Small-load fees. Ready-mix plants often charge extra for orders under 4 to 5 yards, which raises the per-square-foot cost of small slabs.
Frequently asked questions
How much does a concrete slab cost?
A 20 × 20 foot (400 square foot) slab typically costs about $2,300 to $4,000 at 4 inches thick with a gravel base, and $3,100 to $5,200 at 6 inches with reinforcement.
How much does concrete cost per square foot?
Plain 4 inch concrete typically costs $5 to $8 per square foot installed, 6 inch reinforced concrete $7 to $11, and stamped concrete $10 to $19.
How much does a 10x10 concrete slab cost?
A 10 × 10 slab is 100 square feet, so about $575 to $1,000 at 4 inches with a gravel base. Small jobs often carry a minimum charge, which can push it higher.
Is stamped concrete worth it?
Stamped concrete costs about twice as much as plain concrete but less than most natural stone or paver patios. It needs resealing every two to three years to keep its color.
About these figures
General U.S. estimates for installed cost, not quotes. We compared them with HomeGuide's thickness table (about $6–$8 per sq ft for 4 in and $8–$10 for 6 in) and Angi's stamped concrete range. Last reviewed November 2026. Your price depends on your home, your region and the contractor, so treat this as a budget range and compare it with written quotes.