Concrete Bag Yield Chart
This chart shows how much cured concrete each bag size produces. Use it to quickly estimate bag counts for your project.
Standard Bag Yields
| Bag Weight | Yield (cu ft) | Yield Formula | Bags per Cu Ft |
|---|---|---|---|
| 40 lb | 0.300 | 40 ÷ 133.4 | 3.33 |
| 60 lb | 0.449 | 60 ÷ 133.4 | 2.23 |
| 80 lb | 0.599 | 80 ÷ 133.4 | 1.67 |
Coverage per Bag at Common Depths
| Depth | 40 lb Bag | 60 lb Bag | 80 lb Bag |
|---|---|---|---|
| 2" | 1.8 sq ft | 2.7 sq ft | 3.6 sq ft |
| 4" | 0.9 sq ft | 1.3 sq ft | 1.8 sq ft |
| 6" | 0.6 sq ft | 0.9 sq ft | 1.2 sq ft |
Quick Reference: Bags per Cubic Yard
| Bag Weight | Bags per Cu Yd (27 cu ft) |
|---|---|
| 40 lb | 90 bags |
| 60 lb | 61 bags |
| 80 lb | 46 bags |
How the Yield Is Calculated
The yield formula is: bag yield = bag weight ÷ 133.4. The constant 133.4 is an empirical ratio derived from manufacturer specifications (Quikrete, Sakrete). It represents the ratio of dry bag weight to the volume of cured concrete the bag produces.
This is NOT the density of cured concrete (which is ~143-150 lb/cu ft including water weight). The 133.4 constant accounts for the water added during mixing — the bag's dry weight produces a larger volume of wet/cured concrete.
Manufacturer Yields vs Formula
The formula produces yields that match manufacturer specifications within 0.001 cu ft:
| Bag | Formula Yield | Manufacturer Spec | Difference |
|---|---|---|---|
| 40 lb | 0.2999 | 0.30 | 0.0001 |
| 60 lb | 0.4498 | 0.45 | 0.0002 |
| 80 lb | 0.5997 | 0.60 | 0.0003 |
Use the Calculator
The Concrete Bag Calculator uses these exact yields to calculate bag counts. For general-purpose concrete estimation (cubic yards + bags), use the Concrete Calculator.