Concrete Calculators
Plan any concrete pour with confidence. Our concrete calculators turn your measurements into cubic yards, bag counts, and a ready-mix cost estimate in seconds — whether you're pouring a slab, setting fence posts, or forming footings. Below you'll find every concrete estimating tool plus practical guides on coverage, bag counts, and how much concrete you really need.
Concrete calculators
What you can estimate
- Cubic yards of ready-mix for slabs and patios
- Number of 60 lb and 80 lb bags
- Concrete for footings, columns, and post holes
- Material cost before you order
How to estimate concrete for any project
Every concrete estimate starts with volume. Measure the length, width, and thickness of your pour in feet, multiply them together for cubic feet, then divide by 27 to get cubic yards — the unit ready-mix is sold in. A 10 × 10 ft slab at 4 inches thick works out to about 1.23 cubic yards. Because subgrade is never perfectly level and some concrete is always lost to spillage, add 5–10% to whatever the math gives you.
The calculators on this page handle that arithmetic for you and go a step further, converting the volume into the number of 60 lb or 80 lb bags for small jobs and a ready-mix cost range for larger ones. That makes it easy to decide between mixing bags by hand and ordering a truck.
What drives concrete cost
Ready-mix concrete runs roughly $120 to $165 per cubic yard for the material alone, but the delivered, finished price is higher once you add labor, base prep, reinforcement, and any decorative finish. Knowing where the money goes helps you read a contractor quote and spot where you can save.
| Cost factor | Typical impact | Notes |
|---|---|---|
| Ready-mix material | $120–$165 / yd³ | Base cost before labor |
| Labor & finishing | $2–$5 / ft² | Forming, pouring, screeding, finishing |
| Gravel base | $1–$2 / ft² | Compacted sub-base for drainage |
| Reinforcement | $0.15–$0.30 / ft² | Rebar or wire mesh |
| Decorative finish | +$3–$8 / ft² | Stamped, stained, or exposed aggregate |
Slab, footing, or bags — which tool to use
- Slabs and patios: use the concrete calculator with your length, width, and 4-inch thickness.
- Driveways and garage floors: bump the thickness to 5–6 inches for vehicle loads.
- Footings and post holes: enter the footing depth as the thickness and sum each run.
- Small repairs: the bag counts tell you exactly how many 60 lb or 80 lb bags to buy.