How Many Bags of Concrete Are in a Cubic Yard?

Short answer: about 45 × 80 lb bags, or 60 × 60 lb bags, make one cubic yard of concrete. A cubic yard is 27 cubic feet, and each bag of pre-mix yields a fixed volume once mixed with water. Divide 27 by the bag yield and round up.

Concrete bags needed per cubic yard by bag size
Bag size Yield per bag* Bags per cubic yard
40 lb 0.3 cu ft 90
50 lb 0.375 cu ft 72
60 lb 0.45 cu ft 60
80 lb 0.6 cu ft 45

*Yields from QUIKRETE® Concrete Mix (No. 1101) product data. Other brands are very close, but check the bag if you need precision.

Worked example: a 10 × 10 ft slab at 4 inches

Volume = 10 ft × 10 ft × (4 ÷ 12) ft = 33.3 cubic feet = 1.23 cubic yards. At 0.60 cu ft per 80 lb bag, that is 33.3 ÷ 0.60 = 56 bags. Add 5–10% for waste and you'd buy about 60 bags — or simply order 1.4 yards of ready-mix.

Skip the hand math: the concrete calculator does the conversion, adds a waste margin, and shows every bag size at once.

When bags stop making sense

Mixing 45+ bags by hand is a full day of heavy work and each batch varies slightly. Most pros switch to ready-mix delivery somewhere around one cubic yard. Ready-mix also arrives at a consistent strength, which matters for structural slabs and driveways.

Frequently asked questions

How many 80 lb bags of concrete are in a yard?

About 45 bags. An 80 lb bag yields roughly 0.60 cubic feet, and a cubic yard is 27 cubic feet: 27 ÷ 0.60 = 45.

How many 60 lb bags of concrete are in a yard?

About 60 bags. A 60 lb bag yields roughly 0.45 cubic feet: 27 ÷ 0.45 = 60.

Is it cheaper to buy bags or order ready-mix?

For a full cubic yard or more, ready-mix delivery is usually competitive with bags once you count your time and mixing equipment — and the quality is more consistent for large pours. Bags win for small jobs and repairs.

Last reviewed on 2026-07-02. Planning estimates only — confirm quantities with your supplier before ordering.