AreaMapFence calculator
Enter the total length of your fence line and how far apart the posts go. The calculator works out the posts, rails, privacy pickets and post concrete for a wood or vinyl fence.
How the fence is calculated
- Fenced length is the fence line minus the gate openings.
- Sections are the fenced length divided by the post spacing, rounded up.
- Posts are one per section, plus one to end each run, plus one for every corner and gate.
- Rails are the sections times the rails per section. Use 2 rails up to 4 ft high and 3 rails for a 6 ft privacy fence.
- Pickets fill the fenced length side by side with a ⅛ in gap: about 2.1 pickets per foot at 5½ in wide.
- Concrete: a 4×4 post in a 10 in hole 3 ft deep takes about 1.4 ft³ of concrete, or two to three 80 lb bags.
Example: 150 ft of 6 ft privacy fence with posts every 8 ft, 2 corners and one 4 ft gate is 146 ft of fence in 19 sections: 23 posts, 57 rails, 312 pickets and 58 bags of concrete.
Typical post spacing
| Fence | Post spacing |
|---|---|
| Wood or vinyl privacy | 6 to 8 ft |
| Chain link | 8 to 10 ft |
| Woven field fence | 10 to 12 ft |
| Barbed wire | 12 to 16 ft |
| High-tensile wire | 20 to 30 ft |
Measure the fence line first
The number everything depends on is the length of the fence line. Walking it with a tape is slow, and property lines rarely run straight. In AreaMap you trace the fence on a satellite map, mark the gates, and the app gives the length of every side plus this same material list for board, wire, electric, chain link and pipe fences.
Questions
How far apart should fence posts be?
Usually 8 ft for wood and vinyl privacy fences, 8 to 10 ft for chain link, and 10 to 16 ft for wire fences. Closer spacing makes a stronger fence in wind and soft ground.
How many pickets are in an 8 ft section?
About 17 to 18 pickets 5½ in wide, set side by side with a ⅛ in gap. With 3½ in pickets it’s about 27.
How deep should fence posts be set?
About a third of the post’s height above ground, and at least 2 ft. For a 6 ft fence, set 8 ft posts about 2 to 3 ft deep, below the frost line where the ground freezes.
How many bags of concrete per fence post?
For a 4×4 post in a 10 in wide, 3 ft deep hole, about two to three 80 lb bags. Bigger holes for gate posts take more.