Bagged mix
The homepage calculator converts your concrete volume into 40, 60, 80, and 90 lb bag counts. Edit the yield assumptions if your bag label lists a different cubic-foot yield.
| Bag size | Default yield | Approx bags per cubic yard | Best use |
|---|---|---|---|
| 40 lb | 0.30 ft3 | 90 bags | Patch work, tiny pads, setting a post or two. |
| 60 lb | 0.45 ft3 | 60 bags | Small footings, short walks, manageable DIY batches. |
| 80 lb | 0.60 ft3 | 45 bags | Common DIY choice when lifting heavier bags is acceptable. |
| 90 lb | 0.675 ft3 | 40 bags | Fewer bags, heavier handling, often contractor-oriented. |
Bag count equals required cubic feet with waste divided by the bag yield. Always round up to whole bags because you cannot buy a partial bag.
Yields vary by brand, aggregate, mix type, and water ratio. The calculator uses editable defaults, not a guarantee.
One cubic yard is 27 cubic feet. At 0.60 cubic feet per 80 lb bag, that is about 45 bags before waste. For many people, that is the point where a truck quote is worth the phone call.
Decision guide
Bag weight alone is not a universal volume. Read the yield on the exact product data sheet, divide required cubic feet by that yield, then round up to whole bags. Add an allowance for uneven excavation, spillage, form movement, and material left in tools only after the measured volume is correct.
The measured volume is 33.33 cubic feet. At an approximate 0.60 cubic foot yield per 80-pound bag, the base estimate is 55.6, so round to 56 bags before a project allowance. A 60-pound product with about 0.45 cubic foot yield would require roughly 75 bags before allowance.
QUIKRETE and Sakrete describe bag yields as approximate and their calculators account for whole bags. Product type can change yield and minimum application depth. Confirm water, mixing, placement, curing, and safety instructions on the current bag or technical data sheet.