Fence Materials Calculator

Posts, rails, pickets, concrete and stain for your fence run.

How the fence estimate works

Posts are spaced on center — 8 feet is the classic spacing for wood privacy fences, though 6-foot spacing stands up better to wind. Rails run two per section on 4-foot fences and three on 5- to 6-foot. Pickets are counted along the run at their combined width plus gap, and each post hole takes about two 50-lb bags of concrete.

Posts = floor(run / spacing) + 1
Pickets = ceil( run x 12 / (picket width + gap) )

Post depth and wind

Set posts one-third of their above-ground height into the ground — a 6-foot fence wants posts buried about 2 feet, below frost depth where winters freeze. Solid privacy fences catch wind like a sail; in exposed yards, narrower posts spacing (6 ft), deeper footings and a few strategic gaps between pickets all reduce lean and failure.

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Use cases

Privacy fence - 6 ft, three rails, dog-eared pickets, 2 bags concrete per post.
Picket fence - 3–4 ft, two rails, spaced pickets for a classic look.
Garden fence - 3–4 ft, wider post spacing acceptable, lighter materials.
Pool code fence - height and self-closing gates are code matters; verify locally.

Frequently asked questions

How far apart should fence posts be?

8 feet on center is standard for wood privacy fences. Windy sites and tall solid fences benefit from 6-foot spacing; light garden fences can stretch to 10 feet with heavier rails.

How much concrete per fence post?

About two 50-lb bags per post for a typical 4x4 post in a 10-inch hole, more for deep footings in loose soil. Dry-set (pour dry concrete and let ground moisture set it) or wet-set both work; wet-set gives a stronger, more predictable pour.

Estimates only. Check property lines and local fence codes (height, pool barriers) before building.

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Building a fence that stays straight

How to use this calculator

Run a string line along the fence path and measure its length in feet.
Mark gate locations — each gate replaces a fence section and needs two sturdy posts.
Count posts at your spacing (8 ft standard), then rails at two or three per section by height.
Count pickets from their width plus gap; a 5.5-inch picket with a 1-inch gap is 6.5 inches of run each.
Order two 50-lb concrete bags per post plus stain at about 250 sq ft per gallon, both sides.

Quick reference

Fence height	Rails per section	Post spacing
3–4 ft	2	8 ft
5 ft	2–3	8 ft
6 ft privacy	3	6–8 ft
Tall / wind-exposed	3	6 ft

Pro tips

Set corner and gate posts first, run a string between them at rail height, then set line posts to the string — the fence stays straight for free.
Pressure-treated pickets shrink as they dry; gap them slightly now so they do not touch later.
Seal the tops of wood posts (cut end grain drinks water) and keep picket bottoms an inch or two off the soil to slow rot.

Frequently asked questions

Should I use wood or metal posts?

Steel posts (galvanized or powder-coated) outlast wood in ground contact and hold up in wind; wood posts keep a traditional look. Post choice matters more than picket choice for fence lifespan.

How deep do fence posts go?

One-third of the above-ground height as a rule, always below the frost line in freezing climates so frost heave does not lift them. A 6-foot fence typically buries posts 2 to 2.5 feet.

Do I need to stain both sides of the pickets?

Yes — stain penetrates rather than films, and untreated backsides pull moisture unevenly, which causes cupping. Two coats on both sides is the standard first application.