Fence Calculator
Building a fence? Enter the total length, your post spacing and the price per linear foot to find out how many posts, sections and rails you need — and what it will cost.
Estimated Fence Cost
How It Works
A fence is a row of sections between posts, so the maths starts with counting sections: total length divided by post spacing, rounded up, because a part-section still needs a post at each end. Posts are sections plus one, and rails are two per section — the standard arrangement for a wood privacy fence. Total cost is the fence length times your price per linear foot.
Post spacing shapes the whole job. Eight feet is typical for wood fences, because standard rails and panels are made to fit it. Shorter spacing means more posts and more digging, but a stiffer fence; wider spacing saves posts but can leave rails sagging.
Worked Example
A 120-foot fence with 8-foot post spacing needs 120 ÷ 8 = 15 sections. Posts are 15 + 1 = 16 posts, and rails are 15 × 2 = 30 rails. At $25 per linear foot, the estimated cost is 120 × $25 = $3,000. If the same fence were priced at $40 a foot, the cost would rise to $4,800 — the length never changed, only the price per foot.
Assumptions
- The fence runs in a straight line; corners and gates are not counted separately.
- Two rails per section, the standard arrangement for a wood privacy fence.
- Post spacing is the same for the whole fence.
- The price per linear foot is your all-in figure — materials, labour and hardware as you define it.
Fence materials and cost at $25 per linear foot:
| Fence length | Sections | Posts | Rails | Cost |
|---|---|---|---|---|
| 50 ft | 7 | 8 | 14 | $1,250 |
| 100 ft | 13 | 14 | 26 | $2,500 |
| 150 ft | 19 | 20 | 38 | $3,750 |
| 200 ft | 25 | 26 | 50 | $5,000 |
How to Use This Calculator
Enter the total fence length, the post spacing, and your price per linear foot. Results update live, showing sections, posts, rails and the estimated cost. Measure gates separately and subtract their width for the fence-only figure.
Tips and Practical Advice
Set posts in concrete and let it cure before hanging rails — a fence is only as strong as its posts, and the most common failure is a post that leans after the first storm. Check your property line and local rules before you dig: many areas limit fence height or require a permit. And call your local utility-marking service before digging — hitting a buried cable turns a weekend project into an expensive repair.
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