How much concrete do you need?
Enter your measurements to calculate cubic yards, concrete bags, and an optional cost estimate.
Enter your measurements
Measure the inside dimensions of your form. Use depth in inches and choose an extra-material allowance that fits your project.
Your estimate
Enter your dimensions to see your material estimate.
Calculate first. Order with confidence.
Multiply length × width × depth (in feet) for cubic feet, divide by 27 for cubic yards, then apply your chosen allowance. Bag counts use the selected product yield and round up.
Results are estimates, not a substitute for checking on-site dimensions, local requirements, packaging labels, or supplier specifications. Cost fields do not include delivery, taxes or labor unless you incorporate them into your entered price.
Understand the calculationsKnow what is included
Volume conversions use 27 cubic feet per cubic yard. Concrete bag-yield presets come from the QUIKRETE Concrete Mix No. 1101 data sheet. Gravel bulk-density values are editable examples—not universal constants.
View sources and accuracy notesCommon questions
How do I calculate how many cubic yards of concrete I need?
Multiply length in feet by width in feet by depth in feet, then divide cubic feet by 27. The result is cubic yards before any extra material allowance.
How many 80 lb bags are in one cubic yard?
For QUIKRETE Concrete Mix No. 1101, an 80 lb bag yields about 0.60 cubic feet. At that yield, one cubic yard needs 45 bags before waste. Check the specific bag label for other mixes.
Do I have to order both bags and ready-mix concrete?
No. The cubic-yard volume and bag quantity are two ways to purchase the same amount of concrete. They are alternatives, not quantities to add together.
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