Fence Calculator

A fence is a run of posts with rails between them and pickets covering the face. Each part counts differently. Posts divide the run into sections: divide the total length by your post spacing to get the number of sections, then add one, because a fence with five sections needs six posts to close both ends. Common spacings are `6` and `8 ft` on centre — closer for heavy or tall panels, wider for light picket fences.

Rails run horizontally between posts, so the rail count is the number of sections times the rails per section — two for a low fence, three once you pass about `5 ft` tall so the pickets do not bow. The total rail stock is simply the run times the rails per section, since each rail line spans the whole fence. Pickets cover the face: add a picket's width to the gap you want between them, divide the run by that, and round up. A butted picket fence uses gap zero; a spaced picket or shadowbox opens the gap.

Enter the run, pick your post spacing, picket width, gap, and rails per section, and the tool returns posts, rails, pickets, and the linear feet of rail. It counts material for a straight run on flat ground; add posts and rails for each corner, gate, and grade change, and buy a few extra pickets for waste and the odd cull.