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LS Building Products
LS Building Products

Fence Post Depth Calculator

Fence Post Depth Calculator

Post dimensions

in

in

in
  Using default rule of thumb: depth ≈ 1/3 of height (D = 0.333 × H). Adjust above if needed.
 

This calculator is for general informational purposes only. Verify all results with a licensed contractor or structural engineer. Actual requirements vary with frost depth, soil type, wind/snow loads, fence type, post size/material, and local code.

Key Features

✔ Interlinked fields — enter post length, post height, or post depth and the other values update automatically.
✔ Adjustable depth-to-height ratio — default rule of thumb is depth ≈ 1/3 × height; enable the option to use your own ratio.
✔ Wide unit support — inches, feet, yards, millimeters, centimeters, meters, plus compound entry ft/in and m/cm.
✔ Smart input handling — accepts compound formats (e.g., “8 6” for 8 ft 6 in) and formats results with 1/4-inch or 0.1-cm precision.
✔ Instant conversions & hints — automatic unit conversion with helpful notes under the results.
✔ One-click sharing — copy a clean summary of inputs and outputs for quotes or site notes.
✔ Clear / reload controls — reset fields or reload the calculator at any time.

How to Use It

  1. Enter any one value:
    Provide post length, post height, or post depth and choose the unit. The calculator fills in the other two using the default ratio (depth ≈ 1/3 × height).
  2. Refine with your ratio (optional):
    Check “Modify the depth-to-height ratio” and enter a custom value (e.g., 0.4). Results update instantly using depth = ratio × height and length = height + depth.
  3. Switch units anytime:
    Change the unit for any field — values convert automatically. Compound entries like 8 6 (ft/in) and 2 40 (m/cm) are supported.
  4. Share or reset:
    Click “Share result” to copy a summary. Use “Clear all fields” to reset inputs or “Reload calculator” to start fresh.

Set Posts with Confidence

The Fence Post Depth Calculator speeds up planning by relating post height, depth, and total length with practical rules of thumb. For permitted work or challenging conditions, confirm final dimensions with local code or a qualified professional.

Start planning smarter with the Fence Post Depth Calculator today.

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