Post Spacing Calculator

Calculate deck and fence post layout and spacing.

Scratchpad (not saved)

ft

Total fence or deck run length

ft

Maximum spacing between posts

ft
ft

What This Calculator Does

Calculate deck and fence post layout and spacing.

It combines Total Length, Max Spacing, Post Size, Post Hole Depth to estimate Number of Posts, Actual Spacing, Number of Sections.

Formula & Method

Sections are Sections=\left\lceil\frac{Length}{Spacing_{max}}\right\rceil and posts are Posts=Sections+1. Actual spacing is Spacing_{actual}=\frac{Length}{Sections}. Concrete bags are Bags=Posts\cdot BagsPerPost.

Notation used in the formulas: R = Number of Posts; x_{1} = Total Length; x_{2} = Max Spacing; x_{3} = Post Size; x_{4} = Post Hole Depth; x_{5} = Above-Ground Height.

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

  • Total Length: Total fence or deck run length
  • Max Spacing: Maximum spacing between posts
  • Post Size: Used directly in the calculation.
  • Post Hole Depth: Used directly in the calculation.
  • Above-Ground Height: Used directly in the calculation.

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