Fence Picket Calculator — Pickets, Posts & Rails
Plan a picket or board fence. Enter the run length and your picket spacing, and this calculator counts the pickets, posts, rails, and concrete bags for setting the posts.
How to use this calculator
- Enter the total fence length in feet.
- Choose your picket width and the gap between pickets — use 0 for a solid privacy fence.
- Set post spacing (8 ft is standard) and the number of rails per section.
- The concrete estimate assumes about two 50–60 lb bags per post hole; deeper holes need more.
The formula
Pickets fill the run, while posts and rails form the frame.
Pickets = fence length (in) ÷ (picket width + gap), rounded up.
Sections = fence length ÷ post spacing. Posts = sections + 1. Rails = sections × rails per section.
Concrete ≈ 2 bags per post hole for a standard 4×4 post set 2 feet deep.
Worked example
A 100 ft solid fence, 5.5 in pickets, no gap, 8 ft post spacing, 3 rails.
Pickets = (100 × 12) ÷ 5.5 = 218.2 → 219 picketsSections = 100 ÷ 8 = 12.5 → 13 sectionsPosts = 13 + 1 = 14 postsRails = 13 × 3 = 39 rails
A 100 ft solid fence needs about 219 pickets, 14 posts, and 39 rails.
Frequently asked questions
How many fence pickets do I need?
Divide the fence length in inches by the picket width plus the gap. For a solid 100 ft fence with 5.5 in pickets that is about 219 pickets.
How far apart should fence posts be?
Eight feet on center is the standard maximum for wood fences. Use 6 ft spacing for tall privacy fences or windy, exposed sites for extra strength.
How much concrete per fence post?
Plan on about two 50–60 lb bags per post for a typical 4×4 post in a 2 ft deep, 8–10 in wide hole. Taller fences and softer soil need deeper holes and more concrete.