How many fence posts do I need?

Divide the fence length by the post spacing and round up to get the number of sections, then add one for the closing post. A 100 ft fence at 8 ft spacing needs 14 posts.

How many pickets do I need?

Divide the fence length (in inches) by the picket width plus the gap between pickets. For a solid privacy fence the gap is 0; for a spaced picket fence add the gap you want.

How far apart should fence posts be?

Wood fence posts are usually set 6–8 feet apart. Closer spacing is stronger and wind-resistant; wider spacing uses fewer posts but needs sturdier rails.

Fence Calculator

Work out the materials for a wood or picket fence. Enter the fence length and post spacing to get the number of posts, rails, and pickets. For an installed-price estimate, see the fence cost calculator.

Fence material calculator

Posts include the closing post. Set the gap to 0 for a solid privacy fence, or a small gap for a picket/spaced style. Leave picket width blank-equivalent (no count) for rail-only fences.

How it's calculated

Sections are the fence length divided by the post spacing, rounded up; posts are the sections plus the closing post. Rails are sections times the rails per section. Pickets are the fence length in inches divided by the picket width plus the gap between pickets.

Frequently asked questions

How many fence posts do I need?: Divide the fence length by the post spacing and round up to get the number of sections, then add one for the closing post. A 100 ft fence at 8 ft spacing needs 14 posts.
How many pickets do I need?: Divide the fence length (in inches) by the picket width plus the gap between pickets. For a solid privacy fence the gap is 0; for a spaced picket fence add the gap you want.
How far apart should fence posts be?: Wood fence posts are usually set 6–8 feet apart. Closer spacing is stronger and wind-resistant; wider spacing uses fewer posts but needs sturdier rails.

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<p style="font:12px sans-serif">Fence calculator by <a href="https://howmanycalc.com/fence-calculator/">HowManyCalc</a></p>
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Last updated June 2026.