Wood Fence Calculator
Posts, rails, and pickets for the whole fence line — then the concrete to set it.
Your fence
Materials list
Generated by AllUnits.io — allunits.io/calculators/wood-fence
How this calculator figures it
Post count is fence length divided by post spacing plus one; rails multiply sections by rails per run — two for 4-foot, three for 6-foot fences. Picket count divides fence length by picket face width plus gap, using actual dressed widths (a 1×6 measures 5½ inches per NIST PS 20), with 5% for cuts and culls.
How it works
Worked example — 100 ft of 6-ft privacy fence at 8 ft spacing with solid 1×6 pickets: ceil(100 ÷ 8) + 1 = 14 posts; 13 sections × 3 rails = 39 rails; 1,200 inches ÷ 5.5 = 219 pickets, plus 5% = 230. Posts are buried one-third of the fence height (minimum 2 ft), so a 6-ft fence takes 8-ft 4×4s.
Wood fence FAQs
How far apart should fence posts be?
8 feet maximum with 2×4 rails is standard; 6 feet in high wind or with heavy pickets. General practice.
How many rails?
Two for fences up to 4 feet, three for 6 feet — keeps pickets from cupping.
4×4 or 6×6 posts?
4×4 for fences to 6 feet; 6×6 for taller fences and gate posts.
How many pickets per foot?
Solid 1×6: about 2.2 per linear foot.
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Related calculators & sources
Set the posts with the Fence Post Concrete Calculator — the materials list above links to it with your post count filled in. Tally the lumber with the Board Foot Calculator. Dressed sizes come from NIST PS 20; convert measurements with the length converter.
Estimates for planning and purchasing. Not engineering or code-compliance advice — confirm structural work with your local building department.