Calculators
Concrete Calculator
Estimate concrete for a slab or pad.
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About the Concrete Calculator
Pouring a slab, patio, or footing? Enter the length, width, and thickness and the calculator estimates the concrete you need in cubic yards and cubic feet, plus the number of 60 lb bags. It's the fast way to order the right amount and avoid a second trip to the store.
How to use the Concrete Calculator
- 01Enter your length, width, and thickness.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
How much concrete do I need?
Multiply length × width × thickness (in feet) and divide by 27 for cubic yards. This tool does it and estimates bags.
How many bags in a cubic yard?
A 60 lb bag yields about 0.45 cubic feet, so a cubic yard (27 cu ft) needs roughly 60 bags.