How fence post spacing affects material quantities
A fence run is made of bays between posts. Change the maximum bay length and the post, rail, and picket quantities move with it.
Posts are bays plus one
For a straight filled run, divide the effective length by the maximum permitted spacing and round up to full bays. The posts are the bay count plus one because the run has a post at each end.
Simple straight-run logic
bays = ceiling(effective run ÷ max spacing)posts = bays + 1; rails = bays × rails per bayDeduct gates carefully
A gate opening reduces the filled section but usually introduces its own gate posts and hardware. Treat it as a subtraction from the simple picket and rail run, then check gate components, corners, and returns separately.
Pickets are a pitch decision
Picket width plus the intended gap creates the pitch across the run. The final count must still cover the boundary, so the calculator treats internal gaps separately from the last picket rather than promising a perfect end layout.