How it works
Divide the fence length by the post spacing and round up to get the number of sections. An open run needs one more post than sections because both ends need a post; a closed loop needs the same number of posts as sections.
Wire is the fence length times the number of strands, plus an allowance for wrapping, splices, and cuts. Divide by the roll length and round up for the number of rolls. Corner, end, and gate posts are counted inside the total, not added to it.
Worked example
A 660 ft open fence with 12 ft post spacing, four strands, and 5% allowance:
- Sections = 660 ft ÷ 12 ft, rounded up = 55
- Posts = 55 sections + 1 (open run) = 56
- Line posts = 56 − 2 corner/end/gate = 54
- Wire = 660 ft × 4 strands × 1.05 = 2,772 ft
- Rolls = 2,772 ÷ 1,320 ft, rounded up = 3
| Input | Value |
|---|---|
| Total fence length | 660 ft |
| Post spacing | 12 ft |
| Layout | Open run (two ends) |
| Corner, end, and gate posts (already in the total) | 2 |
| Strands of wire or rails per section | 4 |
| Wire per roll | 1320 ft |
| Waste and overlap allowance | 5 % |
| Result | Value |
|---|---|
| Posts (all) | 56 posts |
| Line posts (not corners, ends, or gates) | 54 posts |
| Sections between posts | 55 sections |
| Wire or rail length with allowance | 2,772 ft |
| Rolls of wire | 3 rolls |
| Rails or boards if one per section per strand | 220 pieces |
Assumptions and limits
- Uniform spacing on a straight or gently turning line. Every corner or gate can add a post or brace assembly, which this counts only as part of the total.
- No spacing recommendation is built in; enter what suits your fence type and stock.
- Slope and terrain lengthen wire runs; measure along the ground where they matter.
Common questions
How many fence posts do I need?
Divide the length by the spacing, round up, and add one for an open run. For example, 660 ft at 12 ft spacing is 55 sections and 56 posts.
How far apart should fence posts be?
It depends on the fence type, the stock, and your terrain, so it is left as an input. Follow the fence manufacturer or your extension office.
Do corner posts add to the total?
They are counted inside the total. Brace assemblies and gate hardware are extra and not included.
How much wire should I buy?
Length times strands plus an allowance for wrapping and waste, then round up to whole rolls.
Sources
- Straight-line counting: sections = length ÷ spacing rounded up; open runs have one more post than sections.
- Wire quantity from length × strands with a user-chosen allowance; roll size is an input.
Updated 2026-09-30