Concrete for fence posts
Post Hole Concrete Calculator
Estimate concrete bags, order volume, allowance and material cost for round fence-post holes.
Quantity estimate based on cylindrical volume and editable product yieldUpdated
Project inputs
Calculate post-hole concrete
Example layouts
Results
Concrete to order
Recommended purchase
Quantity estimate only
This calculator estimates concrete quantity for holes whose diameter and depth are already known. It does not choose post spacing, embedment, frost depth, soil support, reinforcement or structural design. Follow the approved plan and local requirements.
Transparent math
How the post-hole estimate is calculated
- 1Find the volume of one cylindrical hole
- 2Add all holes and ordering allowance
- 3Convert volume into bags
References
Product and site checks
Confirm the bag yield on the product label and check underground utilities before digging. Product instructions and local requirements take priority over this estimate.
Common planning questions
Post hole concrete calculator FAQ
How much concrete do I need for a post hole?
Measure the hole diameter and depth, calculate the cylinder volume, multiply by the number of holes and divide by the product yield printed on the bag. Add a practical ordering allowance.
Does post size change the concrete estimate?
Yes. If the post occupies a meaningful part of the hole, subtract the post volume only when you have reliable dimensions. Many estimates conservatively use the full hole volume.
Does this calculator set fence-post depth?
No. Post embedment, frost depth, soil, wind exposure and local rules determine the hole depth and post layout.
Should I use bags or ready-mix?
Compare the bag estimate with ready-mix delivery minimums, short-load fees, access and placement time. Use the current product yield for either comparison.