How Many 80 lb Bags of Concrete in a Yard?

The quick answer and the math

You need 45 bags of 80 lb concrete to make one cubic yard. The number comes from two facts that never change: a cubic yard holds 27 cubic feet, and an 80 lb bag of standard mix yields about 0.60 cubic feet once water is added.

That 45 figure is exact, with no allowance for spillage or an uneven base. In practice, buy a few extra so you never come up short mid-pour, because you cannot top up a slab once it starts to set.

Bag yields and number of bags by size

Not every bag is 80 lb, and the smaller the bag, the more of them a cubic yard swallows. The yield printed on the bag is what matters: it is the volume of finished concrete, not the dry weight. QUIKRETE and Sakrete both list about 0.60 cu ft for an 80 lb bag of standard 4000 psi mix.

So the same cubic yard of concrete is 45 bags of 80 lb, 60 bags of 60 lb, 72 bags of 50 lb, or 90 bags of 40 lb. The 80 lb bag gives you the most concrete per bag and the lowest price per cubic yard, which is why it is the default for anyone mixing by hand.

How many 80 lb bags of Quikrete make a yard

The answer is the same 45 bags, because Quikrete Concrete Mix (product No. 1101) is rated at a 0.60 cu ft yield for the 80 lb bag, exactly the industry standard. Sakrete and other major brands publish the same figure for their standard mixes.

Watch out for specialty products though. Fast-setting, high-early-strength, and crack-resistant blends can yield slightly differently, so always read the yield on the actual bag rather than assuming 0.60. If you would rather skip the arithmetic, enter your slab size in the concrete calculator and it returns the bag count for 40, 60 and 80 lb mix at once.

How many bags for a 10x10 slab

A 10 by 10 ft slab at 4 inches thick needs about 1.23 cubic yards, or 1.36 with a 10% waste allowance. In 80 lb bags that is roughly 62 bags once you round up for waste, or 55 bags at the bare minimum with no contingency.

The volume math is simple: 100 square feet times 0.333 feet of thickness is about 33.3 cubic feet, which is 1.23 cubic yards. If your project is a different size, the broader guide on how many bags of concrete in a yard walks through the same method for any slab.

Is it cheaper to mix your own or buy ready-mix

For anything under about a cubic yard, bags are cheaper; over one to two yards, ready-mix delivery wins. In 2026 a standard 80 lb bag runs about 6 to 7 dollars at Home Depot or Lowe's, so a full cubic yard in bags is roughly 270 to 315 dollars in material alone.

Ready-mix delivered by truck costs about 125 to 175 dollars per cubic yard, nearly half the price per yard. The catch is the 1 yard minimum and a short-load fee of 50 to 100 dollars on small orders, which is exactly why bags still win for posts, repairs and tiny pads.

What is poor man's concrete

Poor man's concrete is the dry pour method: instead of mixing with water first, you spread dry bagged mix over a gravel base inside a form, screed it level, then mist it with water over a couple of days to cure. It is cheap and quick for a small patio or walkway.

It is light-duty only. The dry pour skips the controlled water-to-cement ratio that gives concrete its strength, so it suits foot traffic in mild, non-freezing climates, never a driveway or anything bearing a vehicle. For a structural slab, mix properly and use the bag counts above.

Frequently asked questions

References

• QUIKRETE Concrete Mix No. 1101 data sheet (0.60 cu ft yield)
• Sakrete: Estimating bagged concrete jobs
• Concrete (Wikipedia)
• Concrete cost per yard, 2026 data (Angi)

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