Project calculator
Post Hole Concrete Calculator
Estimate concrete for fence posts, deck posts, and other round-hole jobs using hole diameter, depth, and hole count.
This page keeps the math simple and puts bag counts first, because that is usually the number you care about most for post-setting jobs.
Estimate post-hole concrete
Use the round-hole inputs below, then review total cubic yards and bag counts in the sticky result panel.
Main result
Estimated total concrete
34 80 lb bags
Bag counts are usually the clearest buying output for post-setting jobs, while raw volume stays visible for double-checking the geometry.
Cubic yards
0.75 yd³
Cubic feet
20.36 ft³
Per hole
2.36 ft³
50 lb bags
55
60 lb bags
46
Estimated cost
$221
Before you order
Round-hole geometry is based on a cylinder. If the hole bells out, widens at the base, or includes extra concrete above grade, actual bag needs may run higher than the estimate.
Questions people usually ask next
Still unsure what could change the number or what to check before you order?
Use these answers to clear up the usual sticking points, understand what the result means, and move to the next step with more confidence.
Explore the next useful tool
Still figuring out what to calculate next or what else you should check before you buy?
Start with the tool, converter, or guide that matches your next question. You can compare materials, check another project type, or get quick planning help without losing momentum.
Concrete Slab Calculator
Use slab thickness presets for patios, pads, and standard flatwork.
Post Hole Concrete Calculator
Plan concrete for fence, deck, and mailbox posts.
Material Depth Guide
Check slab and footing depth starting points before you lock in dimensions.
Square Feet to Cubic Yards Converter
Convert square feet and depth, then move into a concrete estimate.