Worked example
A 100 ft, 6 ft tall privacy fence with one 4 ft gate, 5.5 in pickets, 1/8 in gap, posts at 8 ft max and 3 rails: net run = 96 ft = 1,152 in, so pickets = ⌈(1,152 + 0.125) ÷ 5.625⌉ = 205. The gate leaf takes ⌈(48 + 0.125) ÷ 5.625⌉ = 9, for 214 before waste. Sections = ⌈96 ÷ 8⌉ = 12, so posts = 12 + 1 + 1 = 14. Rails = 3 × 12 = 36 2x4s (288 linear ft). Picket screws = 2 × 214 × 3 = 1,284; rail-end screws = 36 × 2 × 2 = 144.
Pickets per 8 ft section and per 100 ft (computed by this calculator)
| Style | Picket and spacing | Per 8 ft section | Per 100 ft |
|---|---|---|---|
| Side-by-side | 5.5 in, tight | 18 | 219 |
| Side-by-side | 5.5 in, 1/8 in gap (privacy) | 18 | 214 |
| Side-by-side | 5.5 in, 1 in gap | 15 | 185 |
| Side-by-side | 3.5 in, 2.5 in gap (classic picket) | 17 | 201 |
| Board-on-board | 5.5 in, 1 in overlap | 22 | 267 |
| Board-on-board | 5.5 in, 1.5 in overlap | 24 | 300 |
Counts are before waste and without gates.
Common mistakes
- Using nominal width (6 in) instead of actual (5.5 in) under-counts by about 8%.
- Forgetting the fence needs one more post than sections, plus one more for each gate.
- Spacing posts farther apart than the rail length. Rails should break at a post center.
- Multiplying picket screws by total rails instead of rails per section.
Frequently asked questions
How many pickets do I need for 100 ft of fence?
About 214 pickets 5.5 in wide with a 1/8 in gap; 219 butted tight; 267 for board-on-board with a 1 in overlap. Add your waste allowance.
How many pickets are in an 8 ft fence section?
18 for a 5.5 in privacy picket (tight or with a 1/8 in gap), 17 for 3.5 in pickets with 2.5 in gaps, 22 for board-on-board with a 1 in overlap.
How far apart should fence pickets be?
Privacy fences use a small gap (about 1/8 in) so boards can move. Decorative picket fences commonly leave 2–3 in. Check local rules for pool barriers.
How many rails does a 6 ft fence need?
Three: top, middle and bottom. The middle rail keeps 6 ft pickets from bowing (Home Depot fence instructions).
How many screws per fence picket?
Two at each rail the picket crosses, so 2 × 3 = 6 per picket on a 3-rail fence. A 100 ft fence with 214 pickets needs about 1,284 picket screws.
What is board-on-board fencing?
Two staggered layers of pickets that overlap each other by about an inch, so you can't see through the fence even after the wood shrinks.