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Fence Post Calculator
Count line posts, corner posts and gate posts for any fence length.
Your result
Enter your numbers and press the button. Your result appears here.
Wood fences usually have posts every 6 to 8 ft because rails come in 8 ft lengths. Chain link posts can be up to 10 ft apart.
How posts are counted
Posts per side = sides length ÷ spacing, rounded up, + 1. Corners are shared between sides. Each gate adds one post so it has a post on both sides.
Example: 100 ft of fence with posts no more than 8 ft apart needs 14 posts: 2 end, corner or gate posts and 12 line posts.
Posts needed at a glance
Worked out with the same settings as the calculator above, changing only the length.
| Length | Posts | Line posts | Sections |
|---|---|---|---|
| 50 ft | 8 | 6 | 7 |
| 100 ft | 14 | 12 | 13 |
| 150 ft | 20 | 18 | 19 |
| 200 ft | 26 | 24 | 25 |
| 300 ft | 39 | 37 | 38 |
| 500 ft | 64 | 62 | 63 |
Rules of thumb
| Item | Typical |
|---|---|
| Depth in the ground | ⅓ of the post length, or below the frost line |
| Hole width | About 3 × the post width |
| Wood post spacing | 6 to 8 ft |
| Chain link line posts | No more than 10 ft |
| T-posts for barbed wire | 8 to 12 ft |
| Field fence | Wood posts 8–10 ft, T-posts 6–8 ft |
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Common questions
How far apart should fence posts be?
Wood fence posts are usually 6 to 8 ft apart. Chain link line posts are no more than 10 ft apart. Wire fences can go wider: T-posts for barbed wire are often 8 to 12 ft apart.
Do corner and gate posts need to be bigger?
Yes. End, corner and gate posts carry the pull of the fence and the weight of the gate, so they are usually heavier and set deeper, and wire fences need bracing there.
Why round up?
If you round down, at least one gap will be wider than your chosen spacing. The calculator spreads posts evenly so no gap is too wide.
Sources
- Home Depot, Chain link fence planning and purchasing guide: https://images.thdstatic.com/catalog/pdfImages/eb/eb410056-2919-4538-b863-3bb02c539842.pdf
- Tractor Supply, T-post spacing guidance: https://www.tractorsupply.com/tsc/product/barbless-cable-3615278