How many fence posts do I need for 100 feet?

With posts every 8 feet, 100 feet takes 13 sections and 14 posts. At 6-foot spacing it is 17 sections and 18 posts. Add posts for extra corners and gates.

How many pickets do I need for a 100 foot fence?

For a privacy fence using 5.5-inch pickets with no gap, 1,200 inches divided by 5.5 is 219 pickets. For 3.5-inch pickets with a 2.5-inch gap it is 200.

How far apart should fence posts be?

Six to eight feet is typical for a wood fence. Eight feet matches standard rail lengths; six feet gives a stronger fence.

Fence calculator

Posts, rails and pickets for this run

Measure the line, choose your spacing and picket, and get a material list you can take straight to the lumber yard or drop into a quote.

Total fence length

Post spacing

6 ft8 ft

Rails per section

2 rails3 rails

Picket style

Privacy, 1×6 tightSpaced picket, 1×4My own sizes

Picket width

Gap between pickets

Corners and ends beyond the first and last

Concrete bags per post

A nominal 1×6 is about 5.5 in wide and a 1×4 about 3.5 in. Nothing you enter is saved or sent.

posts

rails

pickets

sections

bags of concrete

pickets with 5% spare

Counts are for a straight run on level ground. Gates, slopes and odd-length end sections change the list; walk the line before you order.

How the list is worked out

Sections: fence length ÷ post spacing, rounded up.
Posts: one more than the number of sections, plus one for each extra corner or end.
Rails: sections × rails per section, each as long as the post spacing.
Pickets: fence length in inches ÷ (picket width + gap), rounded up.

Worked example. A 100 ft privacy fence with posts every 8 ft and three rails: 100 ÷ 8 = 12.5, so 13 sections and 14 posts. Rails: 13 × 3 = 39. Pickets: 1,200 in ÷ 5.5 in = 218.2, so 219, or 230 with spares.

Choosing post spacing

Eight feet is the usual maximum for a wood fence because rails are sold in 8 ft lengths. Six feet uses more posts but gives a stiffer fence, which matters for tall privacy panels and windy sites.

What the count leaves out

Gates. Each gate needs its own posts, usually heavier, plus hinges and a latch.
Fasteners. Two fasteners per picket at every rail adds up fast: a three-rail fence takes six per picket.
Post length. Posts are set well into the ground. A common rule of thumb is about a third of the post length buried, deeper where the ground freezes; local practice and codes vary.
Before digging. Have underground utilities located and confirm the property line.

The quantity is sorted. Now price the job.

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Posts, rails and pickets for this run

How the list is worked out

Choosing post spacing

What the count leaves out

The quantity is sorted. Now price the job.

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