Fence Post Spacing Calculator.
Split a straight fence run into equal sections without exceeding the maximum post spacing you enter. Get the post count and every center position from the start of the run.
Fence run
Find the fewest equal sections that stay at or below your maximum spacing.
Used only to show the clear opening between post faces.
Post spacing
Enter the straight fence run and your maximum allowed spacing.
This is a geometric layout calculator, not a structural-design recommendation. You choose the maximum spacing based on your fence system and local requirements.
Equal spacing below your maximum
The calculator divides the fence run by your maximum center-to-center spacing and rounds the number of sections up to a whole number. It then divides the full run evenly across those sections, so no section exceeds the maximum you entered.
Posts are placed at both ends of the straight run, which makes the number of posts one greater than the number of sections. Optional post width is used only to show the clear gap between post faces.
Use the result as a layout measurement
The exact center-to-center spacing and position list are intended for marking a straight run. Gates, corners, slopes, wind loading, panel systems and local construction rules can require separate structural decisions, so those are intentionally not guessed by the calculator.
Frequently asked questions
How many fence posts do I need for a straight run?
Enter the run length and maximum post spacing. The tool calculates the minimum number of equal sections that stay within that spacing, then adds one post for the far end.
Why is the exact spacing smaller than my maximum?
The run must be divided into a whole number of equal sections. Rounding the section count up keeps every actual section at or below the maximum you entered.
What is center-to-center post spacing?
It is the distance from the center of one post to the center of the next. That is the spacing used to calculate each post position.
Does this calculator tell me the structurally correct post spacing?
No. It lays out the maximum spacing you provide. Fence material, height, wind, soil, gates and local code can change structural requirements.