Fencing Calculator
Find out how many posts, rails and pickets you need to build your fence.
- Fence posts15 posts
- Rails24 rails
- Pickets330 pickets
- Sections12 sections
How to use
- Enter the total fence length in feet.
- Enter the post spacing in feet (6–8 ft is standard).
- Enter the number of gate openings, rails per section, and picket width.
About this calculator
This fencing calculator works out the posts, rails and pickets for a standard wooden privacy or picket fence. Posts are spaced at equal intervals along the fence run; sections = posts − 1. Each section gets the specified number of rails. Pickets are spaced at the given width with a small gap (about 0.25 in). For gates, each opening needs two gate posts. Always add 10% extra pickets for cuts and waste.
🧮 How it's calculated
- 1Step 1 — Number of sections: Sections = ⌊Total length ÷ Post spacing⌋
- 2Step 2 — Number of posts: Posts = Sections + 1 + (Gates × 2) extra gate posts
- 3Step 3 — Rails: Total rails = Sections × Rails per section
- 4Step 4 — Pickets per section: Pickets = ⌈Post spacing ÷ Picket width⌉
- 5Step 5 — Total pickets: Total = Pickets per section × Sections
Posts = floor(Length / Spacing) + 1; Pickets per section = ceil(Spacing / Picket width); Total pickets = Pickets per section × Sections.
Frequently asked questions
How far apart should fence posts be?+
6 to 8 feet is the standard spacing. Closer spacing (6 ft) is stronger; 8 ft spacing works with heavier lumber.
How deep should fence posts be set?+
One-third of the post's total length should be in the ground. For a 6 ft fence use 9 ft posts set 3 ft deep.
How many rails does a fence need?+
Two rails (top and bottom) is standard for fences up to 4 ft. Use three rails for 6 ft privacy fences.