Fence Calculator
This fence calculator turns your total fence length, post spacing, and gates into a full materials list — posts, panels, rails, pickets, and the concrete bags to set every post. Add 5–10% extra lumber for culls and cuts.
Your project
Your materials
Standard industry formulas with waste included. Always confirm quantities with your supplier.
How many fence posts and pickets do I need?
Divide your total fence length by the post spacing and round up to get sections, then add one end post plus one extra post per gate. Each section takes 2 rails (3 for a 6-foot privacy fence), and standard 5.5-inch pickets with a small gap work out to about 2 pickets per foot of fence. Set every post in two 80 lb bags of concrete, and buy a few extra pickets — every lumber stack has warped boards.
Worked example. A 100 ft fence at 8 ft post spacing with one gate: sections are ⌈100 ÷ 8⌉ = 13, so posts are 13 + 1 end post + 1 for the gate = 15 posts. At 2 rails per section that's 26 rails; pickets run about 2 per foot, so roughly 200 pickets; and at 2 bags of concrete per post you'll need about 30 bags of 80 lb concrete.
| Fence length | Sections @ 8 ft | Posts | Pickets (~2/ft) | Concrete bags |
|---|---|---|---|---|
| 50 ft | 7 | 8 | 100 | 16 |
| 100 ft | 13 | 14 | 200 | 28 |
| 150 ft | 19 | 20 | 300 | 40 |
| 200 ft | 25 | 26 | 400 | 52 |
Posts shown without gates (add one post per gate). Pickets assume 5.5-inch boards with a small gap; concrete at 2 bags per post.