Wood Fence Calculator
Decking & Fencing · Updated July 2026
Enter your fence length, post spacing, and picket width to find how many posts, rails, and pickets your wood fence needs.
Your project
Results
Estimates only. Add extra for waste and confirm with your supplier.
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How many pickets do I need for a fence?
Divide the fence length (in inches) by the picket width. For gaps between pickets, add the gap width to each picket before dividing.
Counting pickets and rails
Divide the fence length (in inches) by the picket width, adding any gap between pickets. Most fences up to 6 feet use 3 horizontal rails per section; taller fences use 4.
Materials that last
Use pressure-treated or cedar for posts and rails, and set posts in concrete. Leave pickets slightly above the ground to slow rot, and seal or stain the fence to extend its life.
How to use this calculator
- 1Enter fence length and post spacing.
- 2Enter your picket width.
- 3Read pickets, posts, and rails.
Frequently asked questions
How many rails per fence section?
Fences up to 6 ft tall typically use 3 rails per section; taller fences may need 4.
How many pickets do I need for a fence?
Divide the fence length in inches by the picket width (plus gap) to get the count.
How many rails does a wood fence need?
Three rails per section for fences up to 6 feet; four for taller fences.
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