Privacy Fence Calculator
Calculate how many posts you need for a 6 ft privacy fence from its perimeter and post spacing, plus total post cost.
How this calculator works
A privacy fence’s solid panels put more wind load on each post than an open-style fence, but the post-count math is the same perimeter calculation: it treats your yard as a rectangle, computes the perimeter, divides by post spacing, and adds one post to close the loop.
Formula: Perimeter = 2 × (Length + Width). Posts = floor(Perimeter ÷ Spacing) + 1.
Worked example
A 40 ft × 30 ft yard enclosed with a 6 ft privacy fence, posts spaced 8 ft apart:
- Perimeter: 2 × (40 + 30) = 140 ft
- Posts: floor(140 ÷ 8) + 1 = floor(17.5) + 1 = 18 posts
- At $15/post, that’s $270.00.
Coverage reference
| Area | Posts (8 ft spacing) |
|---|---|
| 20 x 30 ft | 13 posts |
| 40 x 30 ft | 18 posts |
| 80 x 30 ft | 28 posts |
How to measure your fence line
Measure the two side lengths of the yard area you’re enclosing in feet. Keep the 8-foot spacing for standard privacy panels, but drop to 6-foot spacing (and re-run this calculator with that value) if you’re in a high-wind area or building a fully solid 7-8 ft privacy wall, since it carries meaningfully more wind load per post than a shorter or more open design.
Frequently asked questions
What post spacing works for a 6 ft privacy fence?
8 feet is the standard spacing for pre-built privacy panels and most picket-and-rail privacy fence, matching common lumber lengths for rails without extra splicing. Taller privacy fences (7-8 ft solid panels) sometimes tighten to 6-foot spacing for added wind resistance.
How do I figure out how many pickets I need once I know my post count?
Posts and pickets are separate takeoffs — this calculator gives you the post count for the perimeter, while picket count depends on picket width and the gap between boards. Use the fence picket calculator with the same run length to get the board count for the sections between these posts.
Does a taller privacy fence need closer post spacing for wind load?
Yes — solid privacy fencing acts like a sail, so it takes more wind load per linear foot than an open picket or rail fence. Many installers drop from 8-foot to 6-foot spacing for fences over 6 feet tall, or use larger post sizes (4x4 to 6x6) to compensate, especially in higher-wind regions.
Do gate openings change the post count?
This calculator gives you the baseline perimeter count assuming continuous fence sections. A gate opening still needs a post on each side, which is usually already counted since gates fall at a natural post interval — but oversized gates may need a heavier gate post upgrade rather than an extra post.
How deep should privacy fence posts be set?
A common rule is one-third of the post's total length below grade, so a 6-foot fence with 8-foot posts (leaving 6 ft exposed) sets about 2-3 feet deep in concrete. Deeper is better in high-wind areas or where frost depth is a concern for post heave.
Estimates only. Verify quantities with your supplier before purchasing.