Guides / Materials · Updated
How many 80 lb bags of concrete in a yard?
Yields from the Quikrete Concrete Mix data sheet. Other brands land close, but check the bag.
Short answer
45 bags. An 80 lb bag makes 0.6 cu ft, and a cubic yard is 27 cu ft. That's 3,600 lb of bags to haul and mix by hand.
Bags per yard by size
| Bag | Makes | Bags per cubic yard | Bags per cubic foot |
|---|---|---|---|
| 40 lb | 0.3 cu ft | 90 | 3.3 |
| 50 lb | 0.375 cu ft | 72 | 2.7 |
| 60 lb | 0.45 cu ft | 60 | 2.2 |
| 80 lb | 0.6 cu ft | 45 | 1.7 |
| 90 lb | 0.675 cu ft | 40 | 1.5 |
The table is the plain volume. Add about 10% for a form that bows, a low spot, and what sticks in the wheelbarrow.
Bags or a truck?
Somewhere around 45 bags, which is a full yard, the truck starts to make sense. You'd be lifting almost 2 tons of bags, then mixing them before the first ones set up. A ready-mix truck shows up mixed, and plenty of suppliers will send a short load for a fee.
Count it for your slab
Multiply length by width in feet, then by the thickness in inches over 12. That's cubic feet. Divide by 0.6 for 80 lb bags. A 10 by 10 slab at 4 in is 33.3 cu ft, which is 56 bags before you add any extra.