Concrete Calculator
Estimate how many cubic yards of concrete you need for a slab, and how many bags that equals if you mix your own.
Result
- Volume
- Cubic yards to order
- 80 lb bags
- 60 lb bags
Results are rounded for ordering. Check product labels for exact coverage.
How to use this
An 80-pound bag yields about 0.6 cubic feet; a 60-pound bag about 0.45. Beyond about one cubic yard, ready-mix delivery is usually cheaper and far less work.
Standard slabs are 4 inches thick; driveways for heavy vehicles are often 5 to 6 inches.
Ready to price the job? Try the Concrete Driveway cost calculator for installed prices with materials and labor.
Common questions
How much does a cubic yard of concrete cover?
One cubic yard covers 81 square feet at 4 inches thick, or 108 square feet at 3 inches.
How many 80 lb bags make a yard?
About 45 bags. At that volume, ready-mix is the practical choice.
Should I add waste?
Yes. Uneven subgrade and spillage typically consume 5 to 10 percent extra.