Fence Calculator — How Many Fence Posts and Boards?
Calculate fence posts, rails, and pickets needed for any fence length and style.
Your Results
19
Posts
36
Rails
515
Pickets
288
Rail Lin. Feet
* Add 1–2 extra posts and 5% more pickets for gates and corners.
Materials at Different Post Spacings
| Post Spacing | Posts | Rails | Pickets |
|---|---|---|---|
| 6 ft spacing | 26 | 50 | 515 |
| 8 ft spacing | 19 | 36 | 515 |
| 10 ft spacing | 16 | 30 | 515 |
Formula
Posts = floor(Length ÷ Post Spacing) + 1
Rails = (Posts - 1) × Rail Count
Pickets = ceil(Length × 12 ÷ Picket Width in inches)
Worked Example
Example: 150 ft fence, 8 ft spacing, 2 rails, 3.5 in pickets.
Posts = floor(150÷8)+1 = 19; Rails = 18×2 = 36; Pickets = ceil(150×12÷3.5) = 514
Frequently Asked Questions
How many fence posts for 100 ft at 8 ft spacing?
floor(100÷8)+1 = 13 posts. At 6 ft: 17 posts. At 10 ft: 11 posts.
How many pickets for 100 ft?
3.5-inch pickets: 343. 5.5-inch: 218. Add 5% for gates and corners.
What is standard post spacing?
6 ft for privacy fences. 8 ft is most economical. 10 ft for ranch/farm fencing.
How deep should posts be set?
1/3 of post length in ground. 6 ft fence using 8 ft posts: bury 2.5–3 ft. In frost areas, go below frost line.
Do I need 2 or 3 rails?
Standard 6 ft privacy fence: 2 rails. Over 5 ft tall or high-wind areas: 3 rails for rigidity.