How the fence post spacing calculator works
Enter the fence length and your target maximum spacing. The calculator rounds the bay count up so the final spacing does not exceed your target.
Formula
Posts = ceiling(length ÷ target spacing) + 1
Adjusted spacing = length ÷ (posts − 1)
Example
For 100 ft with an 8 ft target: 13 bays are required, so there are 14 posts and the adjusted spacing is about 7.69 ft.
Assumptions and material notes
This is a layout estimate for a straight run. Corners, gates, end conditions, terrain, and local fence requirements may require additional posts or different spacing.
Frequently asked questions
Is the adjusted spacing always at or below the target?
Yes, when the inputs are valid and the run is divided into whole bays.
Should I use the manufacturer's spacing?
Yes. Structural and product requirements should take priority over a generic planning estimate.
Does this include corner posts?
It estimates a straight run. Add special posts for corners, gates, and ends.
Can I enter decimals?
Yes.
How should I handle gates and corners?
Treat gates, corners, and end conditions separately because they may need different post spacing or hardware.
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Disclaimer: Estimates are for planning purposes only. Actual material requirements may vary based on site conditions, material specifications, installation methods, waste, and local requirements. Always verify quantities with your supplier or qualified professional before purchasing materials.