Project Parameters
Total linear footage of the fence line.
8 ft is standard; 6 ft is recommended for windy areas or heavy panels.
Typical privacy fence is 6 ft; decorative fences are 3–4 ft.
Actual width of pickets (a standard 1x6 board is 5.5 inches wide).
Instant Estimate
Pickets Needed (5% waste)
Horizontal Rails
2 rails per section (8 ft nominal).
Concrete Bags (60 lb mix)
1 to 1.5 bags per post hole (24-36 in depth).
Number of Fence Sections
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Guide
How to calculate fence materials
Building a fence requires calculating four primary components: vertical support posts, horizontal backing rails, vertical pickets or panels, and concrete bags to anchor the posts into the ground below frost depth.
Calculate Post Count
Divide your total perimeter line length by post spacing (usually 8 ft) and add 1 for the end post: (Length / Spacing) + 1.
Determine Rails Count
Multiply the number of fence sections by 2 for fences 6 ft or under, or by 3 for fences 7-8 ft tall.
Count Pickets Needed
Convert fence length to inches (Length × 12), divide by picket width (e.g. 5.5 inches for standard 1x6), and add 5% for cut waste.
Calculate Concrete Bags
Plan for 1 to 2 bags of 60 lb fast-setting concrete per post hole depending on frost depth.
Mathematics
Formulas used
Post Count
Ceil(Fence Length / Post Spacing) + 1Standard 8 ft post intervals require 1 post per section plus the closing terminal post.
Picket Count
Ceil((Fence Length × 12 / Picket Width) × 1.05)Total linear inches divided by actual picket face width plus 5% lumber waste.
Concrete Volume
Posts × 1.5 bags (60 lb)Standard 8-inch diameter hole dug 24–36 inches deep.
Answers & FAQ
Frequently asked questions
How many posts do I need for a 150 ft fence?▼
At standard 8 ft post spacing, a 150 ft fence needs 20 posts (150 / 8 = 18.75 rounded up to 19 sections + 1 end post = 20 posts).
How deep should fence posts be set in the ground?▼
The rule of thumb is at least ⅓ the above-ground height of the fence (a 6 ft fence needs posts set 24–30 inches deep). In northern freeze-thaw zones, posts should extend below the local frost line (36–48 inches).
How much concrete is needed per post?▼
Most standard 4x4 posts in an 8-inch wide hole require 1 to 1.5 bags of 60 lb concrete. For heavy gate posts or deeper holes, use 2 bags.