Fence Calculator
Estimate pickets, posts, rails, and concrete bags for any fence run — with a built-in waste factor and instant, no-sign-up results.
Used to plan rail count and post depth.
A nominal 1×6 picket is 5.5 in wide.
3/8 in (0.375) is a common spacing.
6–8 ft on-center is typical.
2 for 4 ft fences, 3 for 6 ft+.
Add about 10% for culled boards and trimming.
How to Estimate Fence Materials
Start with the posts: divide the fence length by your post spacing and add one for the closing end post. The gaps between posts are the sections, and each section gets the same number of horizontal rails — usually two on a short fence and three on a six-foot privacy fence. Multiplying sections by rails per section by the post spacing gives the total rail linear footage to buy.
For pickets, convert the fence length to inches and divide by the picket width plus the gap between boards, then add a waste factor for culls and trimming. Each post is set in concrete — a standard 4×4 in a two-foot hole takes about two bags of fast-setting mix, so the calculator multiplies your post count by bags per post to size the order.
Frequently Asked Questions
How many fence pickets do I need?
Multiply the fence length by 12 to get inches, then divide by the picket width plus the gap between pickets. With a 5.5-inch picket and a small gap that is roughly two pickets per foot. Add about 10% for waste and culled boards.
How many posts for a fence?
Divide the total fence length by your post spacing — commonly 8 feet — and add one for the final end post. A 100-foot fence at 8-foot spacing needs about 14 posts and creates 13 sections between them.
How much concrete per fence post?
A typical 4×4 wood post in a 10–12 inch hole dug about two feet deep uses around two 50-pound bags of fast-setting concrete. Taller gate posts and sandy or loose soils may need three or more bags each.
Turn Your Measurements Into a Real Floor Plan
Once you know your dimensions, generate a labeled, to-scale floor plan in seconds — then export it to DXF or build it in 3D. No CAD experience needed.
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