Fence Post Spacing: How Many Posts and Sections You Need
Count the sections in each straight run, then account for ends, corners and gates. The examples below show how to avoid counting shared posts twice.
Pick your max spacing first
Spacing is measured from the center of one post to the center of the next. Use the spacing required by the fence design, manufacturer and applicable local requirements. Rail or panel length alone does not establish a suitable spacing for the site's loads. The 8 ft maximum below is an example input, not a design recommendation.
The formula (one straight run)
Sections = Run length ÷ Max spacing, rounded UP to a whole number
Posts = Sections + 1
Actual spacing = Run length ÷ Sections
Example: 150 ft straight run at 8 ft max spacing
Sections = 150 ÷ 8 = 18.75 → round up to 19 sections
Posts = 19 + 1 = 20 posts
Actual spacing = 150 ÷ 19 = 7.89 ft (about 7 ft 10-3/4 in) on center
For a fence system that allows equal bays, dividing the run evenly keeps spacing at or below the maximum. Follow the panel and connection requirements when laying out the bays.
Corners, ends and gates
Break the fence into straight runs between terminal posts: ends, corners and each side of every gate. Work out each run on its own, then add them up.
Line posts in a run = Sections in that run − 1
Total posts = Terminal posts + all line posts
- Corners are shared by two runs, so count each corner post once.
- Gates need a post on each side. The gate opening isn't a fence section.
- Closed loop (fence all the way around, no open ends): posts = total sections, counting each gate as a section.
- Open ends (like a U along three sides): posts = total sections, counting gates, + 1.
Worked example: three-sided backyard with a gate
Example layout, with all run lengths measured between post centers: 100 ft side, 150 ft back and 100 ft side, open where it meets the house. The gate-post centers in the back run are 4 ft apart, leaving fence runs of 71 ft and 75 ft. The 4 ft measurement is a gate bay, not the gate-leaf width or clear opening. Set an actual gate bay from the post, gate and hardware dimensions. Example maximum spacing: 8 ft.
| Run | Length | Sections (round up) | Line posts |
|---|---|---|---|
| Left side | 100 ft | 100 ÷ 8 = 12.5 → 13 | 12 |
| Back, left of gate | 71 ft | 71 ÷ 8 = 8.875 → 9 | 8 |
| Back, right of gate | 75 ft | 75 ÷ 8 = 9.375 → 10 | 9 |
| Right side | 100 ft | 100 ÷ 8 = 12.5 → 13 | 12 |
| Total | 45 fence sections + 1 gate | 41 |
Terminal posts = 2 ends + 2 corners + 2 gate posts = 6
Total posts = 6 + 41 = 47
Check: open-ended layout → 45 sections + 1 gate + 1 = 47 ✓
FAQ
Do I round the number of sections up or down?
Up. Rounding down puts your spacing over max. Then divide the run by the rounded number to get your actual even spacing.
Is the gate width part of the fence footage?
Calculate each fence run to the center of its gate post. If the overall run is measured between post centers, subtract the center-to-center gate bay, not just the clear opening or gate-leaf width. Set the clear opening from the gate and hardware instructions, then account for the post widths to locate the post centers.
Are corner and gate posts the same as line posts?
Often they're heavier or set deeper, because they take more load. Count them separately so they're priced right.
Why is my post count one more than my sections?
On a straight run with two open ends, there's a post at each end of every section, so you always end with one extra.
Quote it in the app
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