BagOrBulk
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Concrete calculator

Size, thickness, done. Bags or a truck?

How it works: Cubic feet = length × width × thickness (in) ÷ 12, plus extra for waste. Bags = cubic feet ÷ bag yield (80 lb = 0.6 ft³). Ready-mix cost includes delivery and any short-load fee.

Project measurements

Your areaDepth guide: 4 in for patios and sidewalks, 5–6 in for driveways and shed bases.
Prices, waste and delivery
Use 0 if you can haul it yourself.
Ready-mix plants charge it on small orders (under 4 yd here).

Prices are typical 2026 US home-center and landscape-yard prices. Type your local quote for an exact answer.

Post holes: enter the hole diameter and depth in inches and the number of holes. Subtract nothing for the post; the extra covers it.

FAQ

How many 80 lb bags of concrete are in a yard?

About 45. A cubic yard is 27 cubic feet and an 80 lb bag yields about 0.6 cubic feet.

How much extra concrete should I order?

5–10% for spillage and uneven ground. The calculator adds 10% by default.

Can it do post holes?

Yes. Choose Post holes and enter the hole diameter and depth in inches and the number of holes.

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Guides

ConcreteHow many bags of concrete?ConcreteBags vs ready-mix concreteGravel & stoneCubic yards to tonsGravel & stoneHow much gravel for a driveway?

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