Fence calculator

Take the fence length without the gate openings, divide by the post spacing and round up to get the number of sections, then add one post to finish the run. Add one more post for every corner and every gate, since a gate needs a post on each side. A straight 100 foot run with posts every 8 feet and no gates is 13 sections and 14 posts.

Convert the fence length without gates to inches and divide by the picket width plus the gap between pickets. A 100 foot run with 5.5 inch pickets and a 0.5 inch gap needs 200 pickets. For a privacy fence with no gap, divide by the picket width alone. Add a few percent for split or warped boards.

Eight feet on center is the most common spacing for wood fence because rails come in 8 foot lengths, and 6 feet is common for taller or heavier panels and for windy sites. Vinyl and metal panels set their own spacing, so use the panel width the manufacturer lists.

Two rails per section is typical for fences up to about 4 feet, and three rails for 5 and 6 foot privacy fence so the pickets do not bow in the middle. Multiply rails per section by the number of sections.

It depends on the hole diameter, the hole depth and the bag size, so check the bag's own chart. As a rough planning number, many 4x4 wood posts in a hole about 10 inches wide take one to two 50 pound bags of fast-setting concrete. Frost depth and local code can call for deeper holes.