Fence Post Calculator
Enter your total fence length and post spacing to get the number of posts and the exact section count.
Enter your measurements to see what to buy.
How to calculate it
Enter your total fence length and post spacing to get the number of posts and the exact section count.
Source: Sections = total length ÷ post spacing; posts = sections + 1 (one extra post at the end). Add a post at each corner and gate.
A 100 ft fence at 8 ft spacing: 100 ÷ 8 = 12.5 → 13 sections → 14 posts. Add posts for each corner and gate.
Want the full step-by-step walkthrough? Read our How to Plan a Wood Fence: Posts, Pickets & Concrete.
Purchasing & waste guidance
- 8 ft post spacing is standard; 6 ft is stronger in high-wind areas.
- Add one post for each corner, end and gate — the calculator counts a straight run.
- Use 4×4 posts for fences up to 6 ft; 6×6 for heavy or 8 ft fences.
- Set posts in concrete — see the Post Hole Concrete Calculator for bag counts.
Assumptions & what’s included
- Fence is a single straight run with uniform post spacing.
- Post count = sections + 1; add posts manually for corners, ends and gates.
- Spacing is center-to-center. Price is per post and optional.
Frequently asked questions
How many fence posts do I need for 100 feet?
At 8 ft spacing, 100 ft of fence has about 13 sections and needs 14 posts. Add one post for each corner, end and gate opening.
How far apart should fence posts be?
8 ft is standard for most wood fences. Use 6 ft spacing in high-wind areas or for taller 8 ft fences to keep the rails strong.
How many posts do I need for a gate?
Each gate needs two sturdy gate posts, usually 6×6, set in concrete. Add these to the line-post count from the calculator.
Related guides
Step-by-step project guides that use this calculator.