Fence Post Concrete Calculator
Bags per post hole and total for the fence run.
Typical 250×600 hole around a 100 post: ~23 L ≈ 1.5 bags. Crown the concrete above grade and slope it away — water pooling at the post line is what actually kills fences.
Formula
Fence Post Concrete Calculator is a free fence post concrete for civil engineers, contractors and quantity surveyors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Fence Post Concrete Calculator
Bags per post hole and total for the fence run. The calculation implements V = (hole − post) volume; 80 lb bag ≈ 17 L (Fence trade practice; frost-depth codes). Typical 250×600 hole around a 100 post: ~23 L ≈ 1.5 bags. Crown the concrete above grade and slope it away — water pooling at the post line is what actually kills fences.
How to use Fence Post Concrete Calculator
- 1Enter Hole diameter in mm (Rule: 3× post width).
- 2Enter Hole depth in mm (⅓ of post height; below frost line).
- 3Enter Post width/diameter in mm.
- 4Enter Number of posts.
- 5Read Concrete per hole, Total 80 lb bags instantly — no submit button needed.
- 6Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Fence Post Concrete Calculator?
- ✓Implements the standard formula — V = (hole − post) volume; 80 lb bag ≈ 17 L
- ✓Reference cited on-page: Fence trade practice; frost-depth codes
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Fence Post Concrete Calculator use?+
It computes V = (hole − post) volume; 80 lb bag ≈ 17 L, per Fence trade practice; frost-depth codes. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Typical 250×600 hole around a 100 post: ~23 L ≈ 1.5 bags. Crown the concrete above grade and slope it away — water pooling at the post line is what actually kills fences.
Does it include wastage?+
Yes — standard wastage/bulking factors are built in and stated in the formula line, so the quantity is an orderable number, not a bare geometric volume.
Is the Fence Post Concrete Calculator free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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