Fence calculator
How many posts, rails and pickets you need for a wood fence of any length.
Posts
- Rails
- Pickets
How to use it
Enter the total length of fence in feet and how many separate straight runs it's split into. Choose the post spacing, the number of rails per section, and your picket width and gap. The calculator shows how many posts, rails and pickets to buy.
Standard dog-ear pickets are sold as 1 × 6 but actually measure about 5.5 inches wide, which is the default. For a privacy fence with pickets touching, leave the gap at 0.
How it's calculated
- Sections per run = run length ÷ post spacing, rounded up.
- Posts per run = sections + 1, because each run has a post at both ends.
- Rails = sections × rails per section.
- Pickets = total length in inches ÷ (picket width + gap), rounded up.
| Fence | Posts at 8 ft spacing | Rails (2 per section) | Pickets (5.5 in, no gap) |
|---|---|---|---|
| 50 ft, one run | 8 | 14 | 110 |
| 100 ft, one run | 14 | 26 | 219 |
| 150 ft, one run | 20 | 38 | 328 |
Post spacing and setting posts
- 8 ft spacing is the most common for wood fences and matches standard 8 ft rails.
- 6 ft spacing makes a stronger fence and is often used for tall privacy fences or windy sites.
- Post depth: a common rule is to bury about a third of the post's length, and at least below your area's frost line. Check local codes.
- Concrete for posts: use the concrete calculator with Post hole selected. Enter the hole diameter and depth, and the number of posts.
Tips
- Call before you dig. In the US, dial 811 a few days ahead to have underground utility lines marked for free.
- Check property lines and permit rules before setting the first post. Many towns limit fence height and set how far a fence must sit from the line.
- Buy a few extra pickets. Some will be warped, split or need trimming around slopes.