Premixed Bags & Hand Pouring
Concrete Mix & Bag Calculator
Calculate the exact number of 40 lb, 50 lb, 60 lb, or 80 lb premixed concrete bags needed for your pour, along with estimated water volume and cost comparisons against ready-mix delivery.
Premixed Concrete Bags vs. Cement Bags: Crucial Differences
A common mistake among DIYers and homeowners is confusing premixed concrete bags with pure Portland cement bags:
- Premixed Concrete (e.g., Quikrete, Sakrete): Contains a pre-blended ratio of Portland cement, washed masonry sand, and gravel stone aggregate. You only need to add clean water. This calculator uses premixed concrete yields.
- Portland Cement Only (94 lb bag): This is pure hydraulic cement with no sand or gravel. Using cement alone without aggregates will result in severe shrinkage, massive cracking, and structural collapse. To make concrete from scratch, you must blend 1 part Portland cement with 2 parts sand and 3 parts gravel.
Documented Bag Yield Benchmarks
| Bag Weight |
Yield in Cubic Feet |
Bags Needed per 1 yd³ |
Typical Water per Bag |
| 80 lb (36.3 kg) |
0.60 ft³ |
45 bags |
3.0 quarts (0.75 gal) |
| 60 lb (27.2 kg) |
0.45 ft³ |
60 bags |
2.25 quarts (0.56 gal) |
| 50 lb (22.7 kg) |
0.375 ft³ |
72 bags |
1.9 quarts (0.47 gal) |
| 40 lb (18.1 kg) |
0.30 ft³ |
90 bags |
1.5 quarts (0.38 gal) |
When to Switch to Ready-Mix Delivery
If your calculation calls for more than 60 to 75 bags (around 1.5 cubic yards), hand-mixing becomes intensely labor-intensive. Mixing 60 bags of 80 lb concrete means handling 4,800 pounds (2.4 tons) of raw material. Premature setting while you mix subsequent batches can cause weak cold joints. In New York City, ordering ready-mix truck delivery for pours over 1.5 yd³ saves hours and ensures certified 4,000 PSI strength.