Bags of Concrete Calculator
How many 40, 50, 60 or 80 lb bags you need — rounded up, with waste, for any slab or footing.
How many bags of concrete?
Waste & region
Order extra for spillage & uneven subgrade. 10% is typical.
Concrete needed (10% waste in)
1.36 yd³
1.24 yd³ of concrete + waste · 100 sq ft
Bags of concrete needed (rounded up)
62
80 lb
82
60 lb
98
50 lb
123
40 lb
- Ready-mix (delivered)
- $230 – $433
- Bagged mix (80 lb, DIY)
- $341 – $558
- Installed by a pro
- $550 – $1,200
Estimate only — not a quote. Bag counts are rounded up and include a 10% waste allowance.
Concrete 1.36 yd³
Bag yields (cubic feet per bag)
| Bag size | Yield (ft³) | Bags per cubic yard |
|---|---|---|
| 80 lb | 0.600 | 45 |
| 60 lb | 0.450 | 60 |
| 50 lb | 0.375 | 72 |
| 40 lb | 0.300 | 90 |
Yields are the industry-standard figures used by QUIKRETE and SAKRETE concrete mix.
Prices updated January 2026 National US averages · reviewed quarterly
Volumes use standard bag yields and a 10% waste allowance; costs are national US averages that vary by region, mix and finish. See our methodology for exactly how each figure is worked out, or check the reference sources:
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Frequently asked questions
How many bags of concrete do I need?
It depends on the volume and the bag size. An 80 lb bag makes about 0.60 ft³, a 60 lb bag 0.45 ft³, a 50 lb bag 0.375 ft³ and a 40 lb bag 0.30 ft³. Divide your total cubic feet by the bag yield and round up — this calculator does it for all four sizes at once.
How many 80 lb bags of concrete make a yard?
A cubic yard is 27 ft³. At 0.60 ft³ per 80 lb bag that's 27 ÷ 0.60 = 45 bags. You'd need about 60 × 60 lb bags or 90 × 40 lb bags for the same yard.
Does this work for Quikrete and Sakrete?
Yes. QUIKRETE and SAKRETE concrete mix use the same standard yields per bag weight, so the counts here apply to either brand and to store-brand mixes of the same weight.
When is bagged concrete not worth it?
Past about one cubic yard (roughly 45 × 80 lb bags), hauling, mixing and the per-bag price usually make ready-mix delivery cheaper and far less work. Tap the cost breakdown to compare.