Fence Post Spacing Calculator

About this calculator

Fence post spacing works backward from two numbers: the total fence run length and the maximum gap the rail or panel material allows between posts (commonly 6 to 8 feet for wood, tighter for wire mesh). The number of posts needed is the fence length divided by the maximum gap, rounded up, plus one for the closing post at the end; dividing the total length by the number of gaps then gives the exact even spacing that uses every post at the same interval instead of leaving an odd short gap at one end.

DIYers and fencing contractors use this calculation before ordering materials, because buying posts based on a rough guess either leaves you short mid-project or wastes money on posts you did not need, and an uneven final gap looks visibly wrong once the fence is built.

This calculator takes your total fence length and the maximum allowed post gap and returns the exact number of posts and the even spacing between them, so you can order the right materials and mark post locations accurately before you dig a single hole.