FENCE POSTS
About this calculator
This fence calculator estimates the materials you need for a privacy or picket fence: posts, panels, and concrete for setting the posts. Standard wood fence posts are spaced 8 feet on center; vinyl can be 6 or 8 feet depending on the panel system. Each post hole typically takes 1–2 bags of 60lb concrete (for a 4x4 post in a 10-inch-wide hole, 2 feet deep).
How to use this calculator
Measure the total fence run in feet (the property boundary you're fencing, not the perimeter — only the sides you're actually building). Set the post spacing — 8 feet is standard for wood fences and matches the panel size most lumberyards stock. Vinyl fences are 6 or 8 feet depending on the panel system. Tighter spacing (6 ft) costs more in posts and concrete but produces a stronger, more level fence on uneven ground.
Enter the number of gates. Each gate adds an extra post (you need a post on both sides of every gate) and replaces one panel. The calculator returns the post count, panel count, gate post count, and the bag count of 60lb concrete needed to set the posts (at the standard 2 bags per post for a 6-foot privacy fence in a 10-inch hole, 2 feet deep).
Worked example
For a 100 ft fence with 8 ft post spacing and 1 gate:
Posts: ⌈100 ÷ 8⌉ + 1 + 1 (gate) = 13 + 1 + 1 = 15 posts. Panels: 13 − 1 (gate) = 12 panels. Concrete: 15 × 2 = 30 bags of 60lb.
At $25–$40 per 4×4 pressure-treated post and $80–$150 per 8-foot privacy panel, materials run $1,300–$2,400. Add concrete (30 × $5 = $150), gate hardware ($60–$120), and post caps. Total materials around $1,500–$2,700.
A two-person DIY crew typically takes 2–3 days for 100 feet of privacy fence including concrete cure time. Pro install adds $25–$45/linear foot in labor, putting an installed price at $4,000–$7,000 for this run.
Common mistakes & waste factors
Forgetting the corner and end posts. Every change in direction needs a post; the calculator's "+1" covers the end post on a straight run, but for an L-shaped or U-shaped fence, add 1 extra post per corner.
Underestimating concrete. The calculator assumes 2 bags per post for a standard 6-foot privacy fence. For 8-foot fences or windy areas, plan on 3 bags per post. For 4-foot picket fences, 1 bag per post is usually enough.
Skipping the line check. Stretch a string line between corner posts BEFORE digging any intermediate holes. A fence that drifts 6 inches off-line over 100 feet looks crooked from the road and there's no way to fix it short of repulling posts.
Ignoring local setback and HOA rules. Most jurisdictions require 6–12 inches of setback from the property line; HOAs often dictate fence style, height, and color. Check before you dig — fence projects are the most-cited cause of property line disputes.
Rules of thumb
8 ft post spacing is standard for wood fences. 6 ft is stronger and required for vinyl in some regions.
2 bags of 60lb concrete per post for a 6 ft privacy fence in a 10-inch hole, 2 ft deep. Bump to 3 bags for 8 ft fences or windy areas.
End and gate posts should be 6×6 or doubled 4×4 — never single 4×4 — because they take all the lateral load.
Post hole depth = ⅓ of post height above grade. A 6 ft fence needs posts buried 2 feet (8 ft total post length).
Plan for one full day of cure time before hanging panels or gates. Quick-set concrete cuts that to 4–6 hours.
Common questions
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