Construction Calculator - Framing and Woodwork

Fence Calculator

Estimate fence posts or panels from total fence length and spacing.

Reviewed: August 26, 2026

Calculate Fence

For the Fence Calculator, enter total run length, spacing, and extra allowance. It estimates regularly spaced stations along one run and rounds the allowance-adjusted result to a whole count; corners, gates, and end conditions need separate treatment.

Construction measuring tools arranged beside a residential building project

Formula and input notes

Repeated stations = ceil(ceil[run length ÷ spacing] + 1, then apply the entered allowance)

InputPractical note
SpacingThis is the Fence Calculator layout value for spacing; confirm whether the drawing specifies clear or on-center spacing.
Fence Calculator measurement plan showing Total run length feet, Spacing feet, Extra allowance percent

Worked fence example

Fence Calculator example: A 97-ft run at 8-ft spacing gives ceil(97 ÷ 8) + 1 = 14 layout stations. With 5% allowance, the estimate rounds to 15.

Use the count as a baseline

Treat the result as line-post stations, then build separate counts for panels or rails, pickets, gates, concrete, caps, and hardware.

Posts, gates, and field conditions

Corners, gates, rackable panels, slopes, terminal posts, and local maximum spacing rules make a fence more than a simple evenly spaced run.

Questions specific to this calculation

What does one repeated station represent for fence?

Use one straight run at a time and enter the intended post spacing or panel width; add end, corner, gate, and change-of-grade posts from the layout.