Concrete Calculator
Cubic yards, cubic meters, and number of bags — for any slab.
Concrete volume
2.25 m³
- Cubic meters
- 2.25 m³
- Cubic yards
- 2.94 yd³
- 80 lb bags
- 100
- 40 kg bags
- 113
Always add 5-10% for waste, uneven ground, and spillage. Pre-mixed bags are convenient for small pours; anything over ~1 m³ is usually cheaper from a truck.
About this calc
Calculate concrete volume for a slab, pad, or footing. Also shows number of 80 lb / 40 kg bags needed.
FAQ
- How many 80 lb bags make a cubic yard?
- About 40 bags. One 80 lb bag yields roughly 0.6 cubic feet of mixed concrete, and there are 27 cubic feet per cubic yard.
- Should I order bags or a truck?
- Under 1 yd³ (0.76 m³), bags are usually easier and cheaper. Over that, a truck delivery beats hauling dozens of bags — both in price and finish quality.
- How much extra should I order?
- 5-10% over calculated volume. Ground settles, edges aren't perfect, and running short mid-pour wastes a truck's trip.