Concrete Calculator — Cubic Yards of Concrete
Figure out how many cubic yards or 60-lb bags of concrete mix you need for slabs, footings, and columns.
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Your Results
1.23
Cubic Yards
33.3
Cubic Feet
75
60-lb Bags
56
80-lb Bags
* Add 10% overage for waste. Consider ready-mix concrete for pours over 1 cubic yard.
Result Breakdown
Frequently Asked Questions
How many bags of concrete do I need for a 10×10 slab?
A 10×10 ft slab at 4 inches thick requires 1.23 cubic yards — about 75 sixty-pound bags or 56 eighty-pound bags. We recommend adding 10% for overage.
How thick should a concrete slab be?
Residential foot-traffic slabs (patios, sidewalks) should be at least 4 inches thick. Driveways require 5–6 inches. Vehicle or heavy-load slabs need 6+ inches with rebar.
What does a cubic yard of concrete weigh?
A cubic yard of ready-mix concrete weighs approximately 4,000 lbs (2 tons).
Should I use 60-lb or 80-lb bags?
80-lb bags cover more volume per bag, so you buy fewer bags and save money. However, 60-lb bags are easier to handle for one person. For large pours, consider ordering ready-mix concrete instead.
How long does concrete take to cure?
Concrete reaches 70% of its strength in about 7 days and full strength (28-day cure) after one month. Foot traffic is safe after 24–48 hours; vehicle traffic after 7 days.