About Post Hole Concrete Calculator
Estimate only the annular concrete space between a cylindrical hole and the inserted post.
Inputs and calculations stay in your browser and require no signup.
How the calculation works
Planning calculation
Net concrete = cylindrical hole volume − post volume, multiplied by the whole hole count.
How to use this calculator
- 1Enter measured project dimensions and quantities.
- 2Adjust material, spacing, waste or density assumptions to match the project.
- 3Review the live planning quantities.
- 4Round purchasing quantities appropriately and confirm field conditions.
Understanding the result
Post displacement is reported separately and always reduces net concrete relative to an empty hole.
Results use the units shown beside each field and output.
Important limitations
- Actual holes are rarely perfect cylinders and may widen or collapse.
- Use manufacturer bag yield and local footing or frost-depth requirements.
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Frequently asked questions
Does the post reduce concrete quantity?
Yes. Round and rectangular post displacement is subtracted.
Can I enter bag yield?
Yes. Use the cured-volume yield printed by the concrete manufacturer.
Are hole dimensions in inches?
Yes, while results convert to cubic feet and yards.
Use with
These tools support a practical next or previous step in the same workflow.
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