Fence Calculator
Enter the length of your fence to see how many posts, rails and pickets to buy.
These are estimates. Real jobs vary with surface, product and waste, so round up and check your product's label before you buy.
How much fence do I need for a backyard?
Measure the line the fence will follow, add up each side, and subtract gate openings. Posts are normally set 6 to 8 feet apart, and a fence always needs one more post than it has sections. This table uses 8-foot sections and 5.5-inch pickets with a half-inch gap.
| Fence length | Posts | Sections | Pickets (5.5 in) |
|---|---|---|---|
| 50 ft | 8 | 7 | 100 |
| 100 ft | 14 | 13 | 200 |
| 150 ft | 20 | 19 | 300 |
| 200 ft | 26 | 25 | 400 |
How the fence calculator works
Sections are the fence length divided by post spacing, rounded up. Posts are sections plus one. Rails are sections times rails per section, and pickets are the length in inches divided by the picket width plus gap. Gates need their own hardware and extra posts, which are not counted here.
Before you build
Check property lines, HOA rules and permit requirements first. A common guideline is to bury about one third of each post's length, deeper in areas with frost. Use pressure-treated or rot-resistant lumber for posts that go in the ground.
Frequently asked questions
How far apart should fence posts be?
Six to eight feet is typical for wood fences. Closer spacing makes a stronger fence.
How many pickets do I need per foot?
With 5.5-inch pickets and a half-inch gap, you need two pickets per foot of fence.
How much concrete do I need per post?
A typical post hole takes about two 80-lb bags, or three to four 50-lb bags, depending on hole size and post height.