Concrete Bag Calculator
Bags from pour volume — distinct from the yards-focused concrete calculator. Click any i for detail.
Volume & bags
Volume unit
i
Unit
Enter cubic feet or cubic yards. |
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|---|---|
Volume (cu ft)
i
Cu ft
Length × width × depth in feet. |
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Volume (cu yd)
i
Cu yd
Same volume in cubic yards (1 yd³ = 27 ft³). |
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Bag size
i
Bag
Typical yields: 40 lb ≈ 0.30 ft³, 60 lb ≈ 0.45 ft³, 80 lb ≈ 0.60 ft³. |
How to use this calculator
- Choose cu ft or cu yd.
- Enter the pour volume.
- Pick bag size.
- Buy extra for waste — the page rounds up whole bags.
Results explained
Bag concrete is sold by weight with a stated yield in cubic feet. Divide your volume by yield per bag and round up. Ready-mix by the yard is usually cheaper for large pours — use the main concrete calculator when you are thinking in yards and truck minimums.
Quick reference: bag yields
bags = ceil(volume_cuft / yield_per_bag).
| Item | Detail |
|---|---|
| 40 lb | ~0.30 cu ft |
| 60 lb | ~0.45 cu ft |
| 80 lb | ~0.60 cu ft |
| 1 cu yd | 27 cu ft |
Check the bag label — yields vary by brand and mix.
How the estimate is built
cuft = cuyd × 27 if needed; bags = ceil(cuft / yield).
Example scenario
10 cu ft with 80 lb bags (0.60 ft³) → ceil(10/0.60) = 17 bags.
FAQ
How is this different from the concrete calculator?
That page focuses on cubic yards for slabs/footings; this one turns a known volume into retail bags.
Should I add waste?
Yes — many DIYers add 5–10% or an extra bag for spills and over-excavation.
Quikrete vs generic?
Always read the yield printed on your brand.
Can I mix half bags?
You can, but strength consistency is harder — prefer whole bags when possible.