Enter your fence length and post spacing to get how many fence posts, rails and pickets you need to build it.
Start with the total length of the fence in feet and the spacing between posts. Dividing length by spacing gives the number of sections, and each straight run needs one more post than it has sections — so add one for the end post. A 100 foot fence with posts every 8 feet is 13 sections and 14 posts.
Each section carries two or three rails — two for short fences, three for tall privacy fences — so multiply sections by rails per section. For pickets, convert the fence length to inches and divide by the picket width plus the gap between pickets. With 5.5 inch pickets and a 0.5 inch gap, each picket takes up 6 inches, so a 100 foot fence needs about 200 pickets.
This calculator assumes straight, evenly spaced runs. Every corner and every gate needs its own post, so add posts for each one. Gate posts should be heavier and set in concrete to carry the swinging weight without leaning over time.
This is a planning aid. Post, rail and picket counts are rounded estimates for straight runs — actual needs vary with terrain, gates and corners. Always round up and buy a little extra.