Fence Post Calculator

How to use this calculator

1. Add each separate fence run.
2. Enter the maximum desired spacing between posts.
3. Calculate the whole-post count and per-run breakdown.
4. Review endpoint assumptions against the real layout.

How the calculation works

Each run is divided by the entered maximum spacing and rounded upward to a whole number of spaces. One additional post supplies the second endpoint. Counts are summed without sharing corner posts between entered runs.

Formula

Spaces per run = ceil(run length ÷ maximum spacing)
Posts per run = spaces + 1
Total posts = sum of posts for all runs

Worked example

A 20 ft run at an entered 8 ft maximum spacing needs 3 spaces and 4 posts. A separate 10 ft run needs 2 spaces and 3 posts, for 7 posts total.

Project considerations

• The spacing input is a planning assumption and must match the chosen fence system.
• Separate runs each include two endpoints; shared-corner layouts may require adjustment.
• Post size, embedment, footing design, loads, and code compliance are outside this count.

Frequently asked questions