Guide · Home Improvement

How Many Bags of Concrete per Cubic Yard?

How many bags of concrete per cubic yard? It depends on bag weight and yield: roughly 45 of the 80 lb bags, 60 of the 60 lb bags, or 90 of the 40 lb bags fill about one cubic yard before waste—then add ~10% and round up. Use the Concrete Calculator for slab dimensions.

Reviewed / updated August 2026

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Quick answer (before waste)

| Bag size | Approx. yield | Bags per cu yd (exact) | | --- | --- | --- | | 40 lb | 0.30 cu ft | 90 | | 60 lb | 0.45 cu ft | 60 | | 80 lb | 0.60 cu ft | 45 |

After a 10% waste factor, multiply and round up (for example, 45 × 1.10 → 50 of the 80 lb bags per yard).

Open the Concrete Calculator to go from slab L×W×thickness straight to yards and bags.

Worked slab

A 10×10 ft pad at 4 inches ≈ 33.3 cu ft ≈ 1.23 cu yd. With 80 lb bags and 10% waste → about 62 bags.

Read the full workflow in How to estimate materials for any home project or browse Home Improvement calculators.

Draft notes

  • Bag yields vary by brand and mix—check the label.
  • Content status: draft stub — calculator is live; expand with more bag charts later.

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Frequently asked questions

How many 80 lb bags of concrete make a yard?

At about 0.60 cubic feet per 80 lb bag, one cubic yard (27 cu ft) needs 27 ÷ 0.60 = 45 bags before waste. With a 10% buffer, plan on about 50 bags. Always confirm the yield printed on the bag.

Should I buy bags or order ready-mix?

Bags suit small pads and post holes. Once you need close to a cubic yard or more, ready-mix delivery is often cheaper and more consistent—compare your plant’s minimum load to bag totals.