Before you load the truck at the store you need one number: how many bags of concrete in a yard your pour actually calls for. Get the count wrong & the mix stops mid slab & forces a cold joint.
The answer depends on bag size: 45 bags of 80 lb mix 60 of 60 lb or 90 of 40 lb fill one cubic yard. Our mulch calculator runs the same bag count math for garden materials on site before you buy a single bag.
The sections below cover the full chart by bag size the reverse conversion for a single bag & a worked slab example. The concrete bag calculator parent page handles other bag math & the concrete calculator pillar covers ready mix yardage.
Key Takeaways
The core division is 27 ÷ yield
One cubic yard equals 27 cubic feet. Divide 27 by the yield printed on the bag & you have the count: 0.60 cubic feet gives 45 bags of 80 lb mix per yard plus 5 to 10 percent for waste.
Bag size changes the count
Bag counts shift with bag size: 60 bags of 60 lb mix & 90 bags of 40 lb mix fill the same yard. Always read the yield on your bag because some mixes pack denser than others on the shelf.
One bag is 0.022 of a yard
One 80 lb bag holds 0.60 cubic feet which is about 0.022 of a cubic yard. That reverse figure helps when you own a few leftover bags & want to know what volume they cover on your next small pour.
A full yard is 3,600 lb of bags
A full yard from 80 lb bags means handling 45 bags that weigh 3,600 lb together before water. Past one cubic yard most pours switch to a ready mix truck for speed & consistent quality on the job site.
Waste comes before the store trip
Add waste before ordering. Ten extra bags on a yard size job covers spillage uneven subgrade & bags that arrive short. Round every bag count up because partial bags harden before you need them again on the next weekend.
How Many Concrete Bags Make a Cubic Yard?
The quick answer to how many bags of concrete in a yard you need: 45 bags of 80 lb mix 60 of 60 lb or 90 of 40 lb fill one cubic yard of space before any waste is figured.
Bag size | Yield per bag | Bags per cubic yard |
80 lb | 0.60 cu ft | 45 |
60 lb | 0.45 cu ft | 60 |
40 lb | 0.30 cu ft | 90 |
Use the table as a starting point not a guarantee. Different products list different yields so confirm the number on your own bag. Sakrete publishes 45 bags of 80 lb mix per yard on its site for its high strength mix.
Another way to sanity check the count: one yard covers about 81 square feet at 4 inches thick. If your slab area divided by 81 lands near your yard estimate the bag count on the shelf should line up too.
How Many 80 lb Bags of Concrete in a Yard?
An 80 lb bag yields 0.60 cubic feet of mixed concrete so 27 divided by 0.60 equals exactly 45 bags. Sakrete states the same figure directly: it takes 45 bags of 80 lb mix to hit a cubic yard dead on.
Those 45 bags hold 3,600 lb of dry mix before water which is why full yard pours usually switch to a truck. For smaller pads buying 45 bags still works provided you have help & a mixer ready to go.
The 80 lb bag of concrete page covers yield coverage by depth & water per bag in detail for that specific size.
How Many 60 lb Bags of Concrete in a Yard?
A 60 lb bag yields about 0.45 cubic feet so one yard needs 60 bags. The math is 27 divided by 0.45. Counts differ across brands so treat 60 as the standard figure then verify your bag label before buying.
Sixty pound bags cost less each but need more trips to the store & more lifting. For a yard sized job the 80 lb size saves time while 60 lb bags suit small patch repairs where you only need a few.
How Many Bags of QUIKRETE in a Yard?
QUIKRETE Concrete Mix No. 1101 follows the same yields: 45 bags of the 80 lb size fill a cubic yard. Run the brand's own calculator to double check since specialty bags for fast set or high strength vary in yield.
How Many Yards Is an 80 lb Bag of Concrete?
Flip the question around: one 80 lb bag gives 0.60 cubic feet & 0.60 divided by 27 equals about 0.022 cubic yards. That means roughly 45 bags stack up to one full yard of mixed concrete ready to pour.
The Weight Test: Carrying a Yard in Bags
Here is the part nobody puts in a chart: one cubic yard of typical concrete weighs about 4,050 lb once mixed using the common 150 lb per cubic foot figure. That weight decides how you move it around the job.
Forty five bags alone hold 3,600 lb of dry powder before any water joins in. Carrying them from the truck to the pad in summer heat is a full afternoon of work for two people not one person alone.
Use that weight as your tipping point. Under half a yard bags make sense between half & one yard the choice is close & past one yard a ready mix truck almost always wins on labor & your back too.
How to Calculate Bags of Concrete for a Slab?
Take a 10 by 10 foot slab at 4 inches thick. Ten times ten gives 100 square feet times 4 divided by 12 gives 33.3 cubic feet which is about 1.24 cubic yards of concrete before any waste allowance.
Divide 33.3 cubic feet by the 0.60 yield & you get 56 bags. Round up & add 10 percent so buying about 62 bags covers spillage & the odd bag that arrives short at the store on your first trip.
Thickness moves the count fast. The same 10 by 10 slab at 6 inches holds 50 cubic feet or about 1.85 yards which needs 84 bags of 80 lb mix before the waste allowance is added to your order. The concrete slab calculator parent page runs this volume math for any pad size.
Bagged Concrete or Ready Mix
Past one cubic yard the calculation stops being about math & starts being about labor. Suppliers usually deliver a minimum of one yard anyway so a bag order at that scale doubles your work for very little saving overall.
Under a yard bags win on delivery minimums & scheduling since you buy only what the pour needs. Compare the total: bags at store prices against a ready mix quote with the delivery fee included before you make the call. Our concrete delivery cost page breaks down those fees.
Conclusion
How many bags of concrete in a yard comes down to yield: 45 bags of 80 lb mix 60 of 60 lb or 90 of 40 lb fill 27 cubic feet. Run the division on your own bag first.
Then size the job add the waste allowance & round every count up. Once the total passes one yard a ready mix truck usually costs less than carrying 45 bags across the yard yourself on a hot summer weekend.
FAQs
How many bags of concrete make one cubic yard?
One cubic yard holds 27 cubic feet. With an 80 lb bag yielding 0.60 cubic feet you need 45 bags while 60 lb bags need 60 & 40 lb bags need 90. Add about 10 percent for waste on the pour.
How many 80 lb bags of concrete in a yard?
Forty five bags. Each 80 lb bag yields 0.60 cubic feet & one yard equals 27 cubic feet so 27 divided by 0.60 gives exactly 45. Sakrete publishes the same 45 bag figure on its site for its mix.
How many 60 lb bags of concrete in a yard?
Sixty bags at the common 0.45 cubic foot yield because 27 divided by 0.45 equals 60. Yields vary between brands so check the label on your bag & recalculate if the printed number differs from the standard figures above.
How many bags of QUIKRETE are in a yard?
QUIKRETE Concrete Mix No. 1101 matches the standard yields: 45 of the 80 lb bags fill one cubic yard. Specialty QUIKRETE products set faster or pack differently so read each bag's yield line before you count your order total.
How many bags of concrete do I need for a 10 by 10 slab?
A 10 by 10 foot slab at 4 inches holds about 33.3 cubic feet. Divided by the 0.60 yield that is 56 bags of 80 lb mix or about 62 once a 10 percent waste allowance is added to the count.
Is it cheaper to buy bags or order ready mix?
Under about one cubic yard bags usually win because suppliers set a one yard delivery minimum. Past that point ready mix typically costs less per yard once you count bag prices trip time & the labor of mixing by hand.
Should I add extra bags for waste?
Yes. Add about 10 percent to every count & round up since bags sell in whole units. A yard sized order becomes about 49 or 50 bags of 80 lb mix instead of 45 covering spills & uneven subgrade.
