How many fence pickets do I need?

Divide the total fence length in inches by the picket width plus gap. For 100 ft of privacy fence with 3.5" pickets and no gap: 1,200 inches ÷ 3.5" = 343 pickets. With 1/4" gap: 1,200 ÷ 3.75 = 320 pickets. Add 10% for waste.

How far apart should fence posts be?

Standard spacing is 6 or 8 feet on center. 6-foot spacing is more common and provides better structural support, especially for tall fences (6 ft+) or in high-wind areas. 8-foot spacing works for shorter fences in calm areas. Gate posts should be no more than 4 feet apart for a single gate.

How many rails per fence section?

Use 2 rails for fences 4 feet and under, and 3 rails for fences 5 feet and taller. The top rail sits 6-8 inches from the top, the bottom rail 6-8 inches from the bottom, and the middle rail is centered between them.

What is board-on-board fencing?

Board-on-board (also called shadowbox) uses overlapping pickets on alternating sides of the rails. It provides privacy from direct angles while allowing airflow. It uses about 50% more pickets than a standard privacy fence because boards overlap by about half their width.

How many nails or screws per picket?

Use 2 fasteners per picket per rail. For a 6-foot fence with 3 rails, that's 6 nails or screws per picket. Use hot-dipped galvanized or stainless steel fasteners to prevent rust stains. Ring-shank nails hold better than smooth nails.

Wood Fence Calculator — Posts, Pickets, Rails & Cost

What Is the Wood Fence Calculator?

The Wood Fence Calculator is a free online tool designed for contractors and DIY builders who need quick, accurate calculations in the construction and building space. By entering your fence style preset, fence length, fence height, you get instant results including posts, rails, pickets. No formulas to memorize, no spreadsheets to build — just enter your numbers and get the answer in seconds. Whether you're a beginner or experienced professional, this calculator saves you time and eliminates guesswork.

Why This Calculation Matters

Getting posts right can make the difference between success and costly mistakes. In construction and building, small errors compound quickly. Manual calculations are error-prone and time-consuming, especially under pressure. This calculator applies proven formulas used by contractors and DIY builders worldwide, giving you confidence that your numbers are correct. Use it to plan your projects with precision and avoid common pitfalls that trip up beginners.

When Should You Use This Calculator?

This tool is most useful when you know your fence style preset and need to find the right posts. It's also great for quick estimates before committing to a decision, and to double-check manual calculations or professional quotes, and when comparing different scenarios side by side. Bookmark this page and come back whenever you need a fast, reliable answer — the calculator is always free and requires no signup.

Wood Fence Calculator

Fence Style Preset

Fence Length (ft)

Fence Height

Post Spacing

Picket Width

Picket Gap (inches)

Number of Gates

Posts

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Rails

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Pickets

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Concrete (80 lb bags)

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Screws / Nails

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Gate Hardware Sets

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Enter fence details to calculate materials.

How to Use This Calculator

Enter Your Fence Style Preset: Start by entering your fence style preset — this is the primary input for the calculation.
Fill In Additional Details: Complete the remaining fields: fence length, fence height, post spacing, picket width, picket gap, number of gates. Each value refines the calculation for greater accuracy.
Click Calculate: Hit the Calculate button to run the numbers. Results appear instantly below.
Review Your Results: Check your posts, rails, pickets. Use these figures to inform your next decision or compare against alternative scenarios.

How to Calculate Wood Fence Materials

The calculator divides fence length by post spacing for posts, multiplies sections by rails per section, and divides total length by picket width + gap for pickets.

Pickets = Fence Length (in) ÷ (Picket Width + Gap)

Posts: fence length ÷ post spacing + 1
Rails per section: 2 for fences ≤ 4 ft, 3 for fences ≥ 5 ft
Pickets: total fence length (inches) ÷ (picket width + gap)
Board-on-board: multiply pickets by ~1.5 for overlap
Concrete: ~1.5 bags of 80 lb per post
Fasteners: 2 per picket per rail (6 per picket for 3-rail fence)

Tips & Considerations

Double-check your fence style preset before calculating — even small input errors can significantly change your results.
Run the calculator with different values to compare scenarios and find the optimal approach for your situation.
Pay attention to both posts and rails — they work together to give you the full picture.
Bookmark this page for quick access next time you need to plan your projects.
If you're unsure about your number of gates, start with a conservative estimate and adjust from there.

Frequently Asked Questions

How many pickets for my fence?

Divide total fence length (in inches) by picket width plus gap. For 100 ft with 3.5" pickets and no gap: 1,200 ÷ 3.5 = 343 pickets. Add 10% for waste.

How far apart should posts be?

6 ft is standard and best for tall or wind-exposed fences. 8 ft works for short fences in calm areas. Gate posts should be no more than 4 ft apart.

How many rails per section?

2 rails for 4 ft and under, 3 rails for 5 ft and taller. Top and bottom rails sit 6-8" from fence edges; middle rail is centered.

How much concrete per fence post?

About 1.5 bags of 80 lb concrete per post for a 4×4 post in a 10" hole at 24" deep. End and gate posts may need 2 bags.

What is board-on-board?

Overlapping pickets on alternating sides of rails for privacy with airflow. Uses about 50% more pickets than standard privacy fence.

How many nails per picket?

2 fasteners per picket per rail. For a 3-rail fence: 6 per picket. Use galvanized or stainless steel to prevent rust.