Concrete Calculator
Calculate concrete quantity from length, width and thickness, add an order overage and compare bulk cubic yards with common bag yields.
Concrete volume2.72 yd³
Before waste2.47 yd³
80 lb bags123 bagsUsing ~0.60 ft³ per bag
60 lb bags163 bagsUsing ~0.45 ft³ per bag
Ready-mix material cost$434.57
Bag yields vary by product and water content. Confirm the manufacturer yield and order policy before purchasing.
How this tool works
Volume = length × width × thickness. Cubic feet are divided by 27 for cubic yards, then the selected overage is added.
Example
A 20 ft × 10 ft slab at 4 inches thick is about 2.47 yd³ before overage.
Common questions
How much extra concrete should I order?
Waste, subgrade variation and supplier minimums vary. A modest overage is common, but use job-specific guidance.
Are bag yields exact?
No. Bag yields are approximate and should be replaced by the manufacturer’s stated yield for the product you buy.