Home Improvement
Gravel Calculator
Estimate gravel area and volume, with weight only when material-specific density is provided.
Concrete Calculator
Calculate concrete volume in cubic feet and cubic yards, with an optional ordering allowance.
Estimate geometric concrete volume for a rectangular slab, pad, or similar placement.
Enter your details
Concrete slab dimensions
Calculated volumeCalculated cubic yardsConcrete volume before wasteOrdering estimate
Your estimate will appear here
Complete the fields and calculate to see a detailed result.
Reading the estimate
Calculated volume describes the measured shape. Ordering quantity adds your chosen allowance.
Formula and methodology
Thickness is converted to feet. Cubic feet = length × width × thickness; cubic yards equal cubic feet divided by 27. Waste multiplies yards by 1 + percentage ÷ 100.
Worked example
A 12 ft by 10 ft slab at 4 inches contains 40 cubic feet or 1.481 cubic yards. Ten percent produces 1.630 cubic yards.
Assumptions and limitations
Excavation variation, forms, subgrade, spillage, delivery increments, reinforcement, mix design, and structural requirements are outside this calculation.
Frequently asked questions
Why divide by 27?
One cubic yard contains 27 cubic feet.
Is 10% always correct?
No. It is an editable starting value.
Does this select a mix?
No. Confirm mix and placement requirements locally.
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Paver Calculator
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