Fence Calculator

Estimate posts, rails and pickets for a length of fence.

Units	Imperial (ft, in)
Fence length	100 ft
Post spacing	8 ft
Rails per section	2
Picket width	3.5 in
Gap between pickets	0.75 in
Gates	1
Cost per section (materials)	$60

Units

Fence length

Post spacing

Rails per section

Picket width

Gap between pickets

Gates

Cost per section (materials)

Posts

13 sections, 26 rails and about 283 pickets. Set posts in concrete about a third of their length deep.

Sections: 13
Rails: 26
Pickets: 283
Materials: $780

The fence line, section by section

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About the Fence Calculator

Divide the run by the post spacing (usually 2.4 m / 8 ft) for sections; posts are one more than sections, plus an extra post for each gate. Pickets = length ÷ (picket width + gap). Bury posts about a third of their length, and check local height limits and boundary rules.

The formula

Posts = ⌈length ÷ spacing⌉ + 1 + gates; pickets = length ÷ (width + gap)

Worked example

Example: Posts = 16

Inputs: Units: Imperial (ft, in); Fence length: 80 ft; Post spacing: 6 ft; Rails per section: 2; Picket width: 2.8 in; Gap between pickets: 0.6 in; Gates: 1; Cost per section (materials): $48.
Formula: Posts = ⌈length ÷ spacing⌉ + 1 + gates; pickets = length ÷ (width + gap)
Result: Posts = 16
Sections: 14
Rails: 28
Pickets: 283

Questions people ask

How deep should posts go?

About one third of the post length, at least 60 cm (2 ft), below frost line in cold climates.

How tall can my fence be?

Rules vary; many areas limit back fences to 2 m / 6 ft without permission.