Fence Calculator — Free Posts, Rails, Pickets & Cost Estimator 2026 | AllInOneTools
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Fence Calculator

Calculate exactly how many posts, rails, pickets, and bags of concrete you need for any fence project. Supports wood, vinyl, and chain link — with full cost breakdown and material shopping list.

Fence Dimensions
ft
Fence Type & Style
gates
Post & Concrete
Cost (per unit)
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$/each
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Fence Calculator: The Complete Guide to Estimating Materials and Cost for Any Fence

Building a fence is one of the most rewarding outdoor projects — it adds privacy, security, property value, and curb appeal. But the material list can be surprisingly complex. Posts, rails, pickets, concrete, screws, caps, and hardware all need to be calculated accurately. This guide covers every fence type and walks you through professional-level estimation.

The Core Fence Formula

Posts = (Total Length ÷ Post Spacing) + 1
Sections = Posts − 1
Rails = Sections × Rails per Section
Pickets = Sections × Pickets per Section
Concrete Bags = Posts × Bags per Post
Worked Example — 150 ft Privacy Fence
150 ft ÷ 8 ft spacing = 18.75 → 20 posts (round up + 1)
19 sections × 3 rails = 57 rails
19 sections × 21 pickets = 399 pickets
20 posts × 1.5 bags concrete = 30 bags
Total materials: 20 posts, 57 rails, 399 pickets, 30 bags concrete

Fence Cost by Type

Fence TypeMaterial $/ftInstalled $/ftLifespan
Wood Privacy (Cedar)$12–$20$20–$3515–20 yr
Wood Privacy (Pressure-treated)$8–$15$15–$2510–15 yr
Wood Picket$5–$12$12–$2210–20 yr
Vinyl Panel$15–$30$25–$4520–30 yr
Chain Link (4 ft)$7–$12$12–$2220+ yr
Aluminum$20–$35$30–$5530+ yr
Wrought Iron$25–$50$40–$7550+ yr

Post Depth and Concrete

Posts must be set deep enough to resist wind loads and frost heave. The standard rule is 1/3 of total post length underground. For a 6-foot fence, use 8-foot posts with 24 inches buried. In cold climates where the frost line is below 24 inches, posts should extend below the frost line — typically 36–48 inches in northern states. Post holes should be 3 times the post width: a 4×4 post needs a 12-inch diameter hole.

Pro Tip — Call Before You Dig
Always call 811 (or your local equivalent) at least 3 business days before digging. They'll mark underground utility lines for free. Hitting a gas, electric, or fiber optic line is dangerous, illegal, and extremely expensive. This applies even for fence post holes — utilities can be as shallow as 12 inches in some areas.

Gates: Planning and Materials

Gates require additional hardware and slightly different construction. A standard gate needs 2 heavy-duty hinges, 1 latch, and a cross-brace for structural support. Gate posts should be 6×6 instead of 4×4 to handle the extra stress of a swinging gate. Standard gate widths: 36–42 inches for pedestrian, 10–12 feet for vehicle/driveway. Double gates should have a drop rod to secure the stationary side.

Check Before Building
Check your local building codes and HOA rules before starting. Most areas require: fences to be on your property (2–6 inches inside the property line), the "good side" facing outward (in many jurisdictions), maximum heights (typically 6 ft backyard, 4 ft front yard), and permits for fences over 6 feet. Some HOAs restrict fence materials, colors, and styles — violations can result in forced removal at your expense.

Wood Selection Guide

Pressure-treated pine is the most affordable option ($8–$15/linear foot) and resists rot for 10–15 years. Cedar is naturally rot-resistant, doesn't need chemical treatment, and weathers to an attractive silver-gray ($12–$20/ft, lasting 15–20 years). Redwood is premium and beautiful but expensive ($20–$30/ft). For posts specifically, use pressure-treated rated for ground contact (look for UC4A or UC4B rating) regardless of what you use for rails and pickets — untreated posts will rot within 3–5 years.

Frequently Asked Questions

How do I calculate how much fencing I need?
Measure total linear feet of fence line. Divide by post spacing (8 ft standard) and add 1 for the end post. Multiply sections by rails per section (2-3) and pickets per section (~21 for privacy). Add 1-2 bags of concrete per post. For a quick estimate: 150 ft fence = 20 posts, 57 rails, ~400 pickets, 30 bags concrete.
How much does a fence cost per foot?
Materials per linear foot: wood privacy $8-$20, wood picket $5-$12, vinyl $15-$30, chain link $7-$15, aluminum $20-$35. Professional installation adds $5-$15/ft for wood, $10-$25 for vinyl. A 150 ft wood privacy fence: $1,500-$3,000 materials, or $3,000-$5,500 fully installed.
How far apart should fence posts be?
8 feet on center is standard for wood and vinyl fences. Chain link uses 10-foot spacing. Never exceed 8 feet for wood privacy fences or they'll sag. Corner posts and gate posts should be 6×6 instead of 4×4 for extra strength.
How deep should fence posts be?
General rule: 1/3 of total post length underground. For 6 ft fence: 24 inches deep with 8 ft posts. In cold climates: below frost line (36-48 inches). Holes should be 3× post width. A 4×4 post needs a 12-inch wide hole. Always use concrete for structural integrity — gravel-only post setting is weaker and shifts over time.
How many bags of concrete per fence post?
4×4 post, 24-inch deep hole: 1 bag of 80 lb. 36-inch deep: 1.5-2 bags. 6×6 post: 2-3 bags. Fast-setting concrete works great for fence posts — pour dry into hole, add water, sets in 20-40 minutes. For 150 ft fence (20 posts): ~30 bags of 80 lb concrete.
How many pickets do I need?
Standard 3.5" dog-ear pickets: ~21 per 8-foot section (with 1/8" gap). Shadow box (alternating): ~28 per section. Multiply by number of sections. 150 ft fence: 19 sections × 21 = 399 pickets. Buy 5-10% extra for waste. Pickets come in bundles — check count before buying.
Do I need a permit to build a fence?
Most areas require permits for fences over 6 ft. Many require them for any fence in front yards. Check local codes for: max height, setback from property line, and required "good side" orientation. HOAs may restrict style and color. Always call 811 before digging to mark utilities — it's free and legally required.