40, 50, 60 & 80 lb bags with water, pallets & labor time
Typical fence post footing: 8–12 in diameter, 24–36 in deep (below frost line where required).
Bagged mixes lose real-world volume to spillage, mix-water variation, and irregular hole or form shapes — even careful crews rarely hit 100% of theoretical yield.
Please enter valid dimensions first.
Total Concrete Needed
–cubic feet
– cubic yards
Bag Size Matrix
Check your product's bag label for its exact yield — fast-setting and high-yield mixes vary by manufacturer.
Water & Labor Estimate
Based on a rule-of-thumb hand-mixing rate of roughly 800 lb of bagged concrete per person-hour. Power mixers, wheelbarrows, and skill level will change this significantly.
Estimate Your Cost
Project Inputs
Estimates are approximate and based on standard bag yields, pallet counts, and manufacturer mix-water guidelines. Always confirm exact yield, water ratio, and pallet quantity on your product's bag label before ordering.
Know exactly how many bags to buy before you leave the store. QuickTonnage's concrete bag calculator turns your slab or post hole into 40, 50, 60, and 80 lb bag counts side by side.
Bag size decides how many bags you'll carry and how many trips to the truck. Here's the quick math.
Heavier bags mean fewer trips but more weight per bag. This concrete bag calculator converts your exact volume automatically, so you don't have to do the math by hand.
About 45 bags of 80 lb concrete mix make one cubic yard.
An 80 lb bag yields about 0.6 cubic feet roughly enough for a 2×3 ft area at 4 inches thick.
It depends on your hole size and post width. QuickTonnage's Post Hole Mode calculates this from your exact hole diameter and depth.
Under 1 cubic yard, bags are usually cheaper and more practical. Above that, a ready-mix truck often costs less per yard.