Concrete Bag Calculator — How Many Bags Do You Need?
Who this is for: For anyone staring at a volume number and a store shelf — post holes, AC pads, mailbox bases, and small pours where you buy by the bag and want the count before driving to the yard.
Work backwards: enter the volume you need in cubic yards or feet and get exactly how many 80, 60, or 40-lb bags to buy — pallet math included.
Quick answer: 45 eighty-pound bags (or 60 sixty-pound bags) make one cubic yard before waste — about 50/66 with a 10% waste factor. Bags make sense under roughly ½ yard; over 1 yard, ready-mix usually wins on price and time.
yd³
Use 0.5 for a small pad, 1 for a yard
80-lb bags
45
27 ft³ needed
60-lb bags
60
easier to carry
40-lb bags
90
small patch jobs
Bag yields per manufacturer published coverage (80 lb ≈ 0.60 ft³, 60 lb ≈ 0.45 ft³, 40 lb ≈ 0.30 ft³). Pours over ~1 yd³ usually cost less from a ready-mix plant. Ballpark tool — confirm quantities with your supplier.
Core facts
80-lb bag
0.60 ft³ yield → 45/yd³
60-lb bag
0.45 ft³ yield → 60/yd³
40-lb bag
0.30 ft³ yield → 90/yd³
Pallet
42 × 80-lb or 56 × 60-lb bags
How many bags of concrete do I need?
Bag math runs on published yields: an 80-lb bag produces about 0.60 ft³ of mixed concrete, a 60-lb bag about 0.45 ft³, a 40-lb bag about 0.30 ft³. Enter the volume you need — in cubic yards if you have it, cubic feet if you computed it by hand — and the calculator divides by yield and rounds up to whole bags, then groups them into 42-bag (80-lb) or 56-bag (60-lb) pallets so you know whether one trip covers it. The crossover to remember: past roughly 1 cubic yard, bag work costs more per yard and takes a crew a full day of mixing where a ready-mix truck finishes in twenty minutes.
Common uses
Counting bags for post holes and footings before a store run
Comparing bag cost per yard against ready-mix pricing
Planning pallet pickups for a small pour day
Splitting a big job into realistic mixing sessions
Frequently Asked Questions
How many 80-lb bags are in a cubic yard?
45 bags before waste (27 ft³ ÷ 0.60 ft³ per bag); 50 bags with a 10% waste factor. One pallet holds 42 bags, so a full yard is just over one pallet.
How many 60-lb bags are in a cubic yard?
60 bags before waste; 66 with 10% waste. Sixty-pound bags are easier to carry but cost more per yard than 80s at most suppliers.
How much does a bag-pour cost vs ready-mix?
As of September 2026 national ballparks, 80-lb bags run $6-8 each — about $300-360 per yard in bags, versus roughly $160-220 per yard for ready-mix delivered (plus minimum-load charges on small pours). Under about half a yard, bags win; over a yard, the truck usually does.
How long does mixing 45 bags take?
With a powered mixer and two people, figure 3-4 minutes per bag from open to wheelbarrow — about 2.5-3 hours for a yard, not counting placement and finishing. By hand in a tub, double it.