How many bags of concrete in a cubic yard?
A cubic yard of concrete is 27 cubic feet, and an 80 lb bag yields about 0.60 cubic feet, so it takes 45 bags of 80 lb to make a yard: 60 bags of 60 lb, 72 of 50 lb or 90 of 40 lb. In metric, a cubic metre needs about 84 bags of 25 kg. Those are exact-volume figures; add 10% for waste and you are buying 50 bags of 80 lb per yard.
Bags per cubic yard, all sizes
The yields are the figures printed on typical pre-mixed concrete bags. Brands differ by a few percent, so check yours: the concrete calculator lets you type in the yield from the bag.
| Bag | Yield (cu ft) | Bags per yard (exact) | Bags to buy | With 10% waste | Dry weight (lb) |
|---|---|---|---|---|---|
| 80 lb | 0.6 | 45 | 45 | 50 | 3,600 |
| 60 lb | 0.45 | 60 | 60 | 66 | 3,600 |
| 50 lb (fast-setting) | 0.375 | 72 | 72 | 80 | 3,600 |
| 40 lb | 0.3 | 90 | 90 | 99 | 3,600 |
How the numbers are worked out
Divide 27 cubic feet by the yield of one bag and round up. For an 80 lb bag that is 27 / 0.60 = 45, so 45 bags. Per cubic foot it is 1.67 bags of 80 lb, 2.22 of 60 lb or 3.33 of 40 lb. Waste is the part everyone forgets: uneven ground, formwork that bows, mix left in the barrow. Ten percent is the usual allowance on small jobs; the tables below already include it.
Bags for common order sizes
Slabs are rarely a round yard. These figures come straight from the calculator with 10% waste, so they match what it shows for a slab of the same volume.
| Volume | 80 lb bags | 60 lb bags | 50 lb bags | 40 lb bags |
|---|---|---|---|---|
| 0.25 cu yd | 13 | 17 | 20 | 25 |
| 0.5 cu yd | 25 | 33 | 40 | 50 |
| 1 cu yd | 50 | 66 | 80 | 99 |
| 1.5 cu yd | 75 | 99 | 119 | 149 |
| 2 cu yd | 99 | 132 | 159 | 198 |
| 3 cu yd | 149 | 198 | 238 | 297 |
A yard of bags is not a yard of ready-mix
Both give you 27 cubic feet of concrete, but they are different products. Bagged mix is a fixed recipe you add water to; the strength depends on how carefully you measure the water. Ready-mix arrives batched at a plant to a specified strength and, for anything structural, that is what an inspector wants to see. Above roughly one cubic yard the truck usually wins on both price and back pain; below it, the short-load fee tips the balance towards bags. Either way, pour a slab in one session so it cures as a single piece.
Metric: bags per cubic metre
Bags of 25 kg yield about 12 litres and 20 kg bags about 10 litres of concrete. A cubic metre is 1,000 litres, or 35.3 cubic feet, so it is about 1.3 cubic yards.
| Bag | Yield (L) | Bags per m³ (exact) | Bags to buy | With 10% waste | Dry weight (kg) |
|---|---|---|---|---|---|
| 25 kg | 12 | 83.3 | 84 | 92 | 2,100 |
| 20 kg | 10 | 100 | 100 | 110 | 2,000 |
Before you buy
- Work out the volume first. The 10x10 slab guide and the 12x12 slab guide have the common sizes already worked out; the calculator does any slab, footing, post hole or column.
- Yields on the bag assume the water quantity on the bag. Sloppy mix does not make more concrete, it makes weaker concrete.
- Have every bag on site before you start. Running out mid-pour is the expensive mistake; two spare bags are cheap.
Frequently asked questions
- How many 80 lb bags of concrete are in a yard?
- 45 bags at the 0.60 cubic feet per bag printed on typical labels (27 / 0.60 = 45). Buy 50 to cover 10% waste. That is about 3,600 lb of dry mix to carry.
- How many 60 lb bags of concrete make a yard?
- 60 bags at 0.45 cubic feet each, or 66 with 10% waste. The 60 lb bag is easier to lift but you handle half as many again as with 80 lb bags for the same yard.
- How many 40 lb bags of concrete in a yard?
- 90 bags at 0.30 cubic feet each, 99 with waste. Small bags make sense for a few post holes or a repair, not for a yard: the cost per cubic foot is the highest of the four sizes.
- How many bags of Quikrete or Sakrete are in a yard?
- The same as any other brand of the same weight: the yield depends on the bag size and the mix, not the name. Quikrete and Sakrete print about 0.60 cubic feet for an 80 lb bag, which gives 45 bags per yard. Some data sheets say 0.59 or 0.61; the difference is one bag in forty-five.
- Is it cheaper to buy bags or order ready-mix for a yard of concrete?
- Per cubic yard, bagged mix usually costs more than ready-mix, and you also mix 45 bags by hand. Ready-mix plants charge a short-load fee under a minimum order (often a few yards), so for exactly one yard the totals can come out close: ask for a delivered price including the fee and compare it with 50 bags, a mixer and a day.
- How many bags of concrete make a cubic metre?
- About 84 bags of 25 kg or 100 bags of 20 kg at the usual 12 and 10 litre yields; 92 and 110 with 10% waste. A cubic metre is roughly 1.3 cubic yards.
More guides
- How many bags of concrete for a 10x10 slab?
Bags of 80, 60 and 40 lb concrete for a 10 x 10 ft slab at 4, 5 and 6 inches with 10% waste, plus the metric 3 x 3 m version in 25 kg and 20 kg bags.
- How many bags of concrete per fence post?
Bags of 80, 60 and 50 lb concrete per 4x4 or 6x6 fence post for 8, 10 and 12 inch holes at 24, 30 and 36 inches deep, plus the metric 100 mm post in 25 kg bags.
- How much concrete for a 12x12 slab? (plus 16x16, 20x20, 24x24)
Cubic yards and bags of concrete for 12x12, 16x16, 20x20 and 24x24 ft slabs at 4 and 6 inches with 10% waste, the 4 x 4 m metric slab, and the point where ready-mix wins.
- How many bags of concrete for a sonotube? 8, 10, 12 and 16 inch
Bags of 80, 60 and 50 lb concrete for 8, 10, 12 and 16 inch sonotubes at 2, 3 and 4 ft, concrete per foot of tube, and 200 to 300 mm forms in 25 kg bags.
Last updated 2026-09-12. Figures are planning estimates from typical product data: check the yield, size or coverage printed on what you buy and round up.