How Many 40 lb Bags of Concrete Are in a Yard?

One cubic yard of concrete takes about 90 bags of 40 lb concrete mix when each bag yields 0.30 cubic feet. If you add a 10% waste factor, plan for about 99 bags.

Use the Concrete Bag Calculator if you want to change the yield, waste factor, bag price, or project dimensions. This guide is the quick 40 lb bag answer for one cubic yard.

For a broader bag-size comparison, see the Concrete Bags per Yard Guide. If you are working from a slab size, the 40 lb Concrete Bag Calculator has more coverage examples.

Quick answer

Common planning estimate:

Always check the yield printed on the actual bag you plan to buy. Fast-setting mixes, repair mixes, and specialty products can vary.

Formula

One cubic yard equals 27 cubic feet.

40 lb bags per yard = 27 cubic feet / 0.30 cubic feet per bag
40 lb bags per yard = 90 bags

If you include waste:

bags to buy = round up(90 x (1 + waste percentage))

With 10% waste:

90 x 1.10 = 99
buy 99 bags

Waste factor examples

For simple forms, 5% to 10% waste is a practical planning range. Use more if the base is uneven, the forms vary in depth, or the pour shape is irregular.

How much does one yard weigh in bags?

One cubic yard using 90 bags of 40 lb mix is:

90 x 40 lb = 3,600 lb of dry mix

With 10% waste, 99 bags is:

99 x 40 lb = 3,960 lb of dry mix

That weight is before water and does not include moving, opening, mixing, and placing each bag. At one cubic yard, 40 lb bags usually create too many bags for a comfortable pour, so compare larger bags or ready-mix delivery using the Ready-Mix vs Bags Calculator.

Cost example

If one 40 lb bag costs $3.50:

90 bags x $3.50 = $315.00 before waste
99 bags x $3.50 = $346.50 with 10% waste

That is material cost only. It does not include tax, tools, mixer rental, base material, reinforcement, delivery fees, labor, or cleanup.

For a fuller cost check, use the Concrete Cost Calculator after you know your bag count.

40 lb bags vs 60 lb and 80 lb bags

40 lb bags are easier to lift, but they create the highest bag count for the same volume. For one cubic yard before waste:

Use 40 lb bags when handling weight matters or the job is small. For a full cubic yard, compare total cost, total mixing time, and whether 60 lb bags, 80 lb bags, or delivery will make the pour easier.

FAQ

How many 40 lb bags are in one cubic yard of concrete?

Using a common 0.30 cubic foot yield, one cubic yard takes about 90 bags of 40 lb concrete mix before waste.

How many 40 lb bags should I buy for one yard with waste?

With a 10% waste factor, buy about 99 bags of 40 lb concrete mix for one cubic yard.

How many cubic feet are in a 40 lb bag of concrete?

A 40 lb bag commonly yields about 0.30 cubic feet of mixed concrete. Check the product bag because yield can vary by mix.

Is one yard of concrete too much to mix from 40 lb bags?

For most DIY pours, 90 to 99 bags is a lot of handling and mixing. Compare 60 lb bags, 80 lb bags, or ready-mix delivery before committing to 40 lb bags.

Next step

Open the Concrete Bag Calculator to calculate your exact bag count, waste, and material cost. Then compare the result with the Ready-Mix vs Bags Calculator before buying.