Concrete Calculator for Post Holes
Use this post-hole concrete calculator for repeated cylindrical holes where slab calculators are not the right shape.
Live estimator
Build the Estimate
Measurement controls, project presets, and a material result card for this calculator.
Formula and Assumptions
Hole volume = pi x radius squared x depth. Multiply by number of holes and divide by bag yield.
- Hole diameter and depth should be measured after digging.
- Local codes may require specific depth below frost line.
Frequently Asked Questions
Is this concrete calculator for post hole exact?
No. It is an estimate based on common project formulas and the assumptions shown on the page. Always confirm package labels and local conditions before buying materials.
Should I add extra material?
Most projects need extra material for cuts, waste, damaged pieces, uneven surfaces, or future repairs. The calculator includes a waste factor where it matters.
Can I print the result?
Yes. Use the print action on the page to keep a simple copy of the inputs, formula, and estimated material list.