Concrete Yardage Calculator
Enter your measurements
Extra to cover cuts, breakage, and mistakes.
Results
- Concrete needed1.36 cubic yards
- Volume36.67 cubic feet
- 60 lb bags82if mixing by bag
- 80 lb bags62if mixing by bag
Estimated cost
per cubic yard of ready-mix, delivered
Material cost covers delivered ready-mix concrete only, priced per cubic yard. Short-load fees ($50–$150) apply when the order falls below the supplier's minimum and are not included in the per-yard rate. Installed figures add labor and finishing and vary with slab thickness — thinner slabs cover more area per yard, so they cost more per cubic yard installed.
Estimate only — prices vary by region, supplier, and season. Get a local quote before buying.
This concrete calculator by the yard converts your slab or footing dimensions — length, width, and thickness — into the cubic yards you need to order, along with equivalent 60 lb and 80 lb bag counts. Concrete is sold by the cubic yard when ordered as ready-mix from a batch plant, and it comes in 60 lb or 80 lb bags at home centers for smaller pours. Knowing your yardage before you call a supplier prevents costly short loads and the delays of waiting on a second truck. Ready-mix suppliers set order minimums and charge a short-load fee — typically $50–$150 — when your order falls below their threshold, commonly around 5 to 7 cubic yards. A standard drum-mixer truck holds 8 to 10 yards. The calculator applies a 10% waste and overage factor by default, which is standard practice for slabs; footings and columns may need slightly less, while irregular shapes or uneven subgrade justify bumping it to 15%.
How it’s calculated
Volume = Length × Width × Thickness, converted to cubic yards (÷27) and to 60 / 80 lb bag counts.
Worked example
For a 30 ft by 20 ft driveway slab poured at 5 inches thick with a 10% overage allowance, the calculator returns 10.19 cubic yards (275 cubic feet) — enough to fill a single ready-mix truck delivery rather than scheduling multiple smaller loads. That same pour would require 612 bags of 60 lb mix or 459 bags of 80 lb mix if you were hand-mixing, which makes the case plain: ready-mix is the practical choice above a few yards.
Inputs
- Length
- 30 ft
- Width
- 20 ft
- Thickness
- 5 in
- Waste / overage
- 10 %
Result
- Concrete needed
- 10.19 cubic yards
- Volume
- 275 cubic feet
- 60 lb bags
- 612
- 80 lb bags
- 459
- Estimated material cost
- $1,426 – $1,884
Materials & pricing near you
Ready-mix concrete is priced per cubic yard and varies noticeably by region and season. Across most US markets in 2026, delivered ready-mix runs roughly $140–$185 per cubic yard, with high-cost metros and high-strength mixes (4,500 PSI and up) pushing higher. Rural areas with fewer batch plants may add a distance surcharge or raise the minimum-load threshold. Prices typically tick up a few percent in spring and early summer when demand peaks. Bag concrete (Quikrete, Sakrete) runs about $5–$8 per 60 lb bag and $6–$9 per 80 lb bag at home centers — fine for fence posts or repairs, but at roughly $220–$290 of material per cubic yard, far costlier than ready-mix for anything over a yard or two.
Frequently asked questions
How do I measure thickness accurately for the calculator?
Measure or mark the planned depth at several points across the form, then use the average. Subgrade is rarely perfectly flat, so a nominal 4-inch slab often averages closer to 4.5 inches once gravel or dirt high spots are accounted for. Rounding up to the next quarter-inch is common practice to avoid running short mid-pour, since concrete fills the deepest low spots first.
What is the standard thickness for a concrete driveway or patio slab?
Residential driveways are typically poured at 4 to 5 inches thick, with 5 inches recommended in cold climates or where vehicles park regularly. Patios and sidewalks commonly use 4 inches. Slabs that bear heavier loads — RV pads, heavy equipment, or garage floors — should be 5 to 6 inches, usually with rebar or wire mesh. Most residential mixes run 3,000 to 4,000 PSI.
How many cubic yards are in a full ready-mix truck load?
Most standard drum-mixer trucks carry 8 to 10 cubic yards, though some suppliers cap loads at 7 yards on certain routes due to axle-weight limits. If your order falls below the supplier's minimum — commonly 5 to 7 yards — expect a short-load fee of $50–$150. Scheduling back-to-back pours, such as a patio and a set of footings, can help fill out a single truck.
When should I use bags instead of ordering ready-mix?
Bag concrete makes sense for pours under about 0.5 cubic yards: fence-post settings, small repair patches, or isolated footings. Above roughly one cubic yard, the labor of mixing dozens of bags and the material cost — bag mix runs about $220–$290 per yard — exceeds ready-mix pricing. For larger slabs, ready-mix also avoids cold joints, which form when one section sets before the adjacent section is placed.