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Fence Calculator

Enter the length of your fence line to find how many posts, rails and pickets to buy. Adjust the post spacing, rails per section, picket width and gap, and add prices for a material cost.

Quick examples

8 ft is standard for wood; 6 ft for tall or wind-exposed fences.

A nominal 6 in picket is 5½ in wide.

0 for a privacy fence.

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Your numbers stay in your browser. Nothing is uploaded.
Pickets219
Posts
14
Sections
13
Rails
26
Material cost
$1,141.75

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    Your recent calculations

    Results you calculate here are kept on this device so you can come back to them.

      Formula

      Sections = fence length ÷ post spacing, rounded up
      Posts = sections + 1
      Rails = sections × rails per section
      Pickets = fence length ÷ (picket width + gap), rounded up

      How to use it

      1. Measure the fence line and enter its total length.
      2. Enter the post spacing and choose the number of rails.
      3. Enter the actual picket width and the gap between pickets.
      4. Enter prices to estimate the material cost.

      Worked examples

      A 100 ft privacy fence with posts every 8 ft, two rails and 5½ in pickets

      Sections
      13
      Posts
      14
      Rails
      26
      Pickets
      219
      Material cost
      $1,141.75

      A 60 ft picket fence with posts every 6 ft, three rails and 3½ in pickets 2½ in apart

      Sections
      10
      Posts
      11
      Rails
      30
      Pickets
      120
      Material cost
      $612.00

      Posts, corners and gates

      The count assumes one straight run. Each separate run needs its own end post, so add one post for every extra run, and add gate posts and gate hardware separately. Divide each run into equal sections rather than leaving a short one at the end.

      A common rule is to bury one third of the post: a 6 ft fence uses 8 ft posts set about 2 ft deep, deeper where the frost line requires. Call 811 before digging in the US so buried utilities can be marked.

      Rails and pickets

      Use two rails for fences up to about 5 ft and three for 6 ft and taller. Rails are sold in lengths matching the post spacing, usually 8 ft. A nominal 1×6 picket is 5½ in wide, and a 1×4 is 3½ in.

      These figures are planning estimates. Local building codes and a qualified professional govern the actual design. Many towns limit fence height and require a permit or a setback from the property line.

      Questions people ask

      How many fence posts do I need for 100 feet?

      14 posts at 8 ft spacing: 100 ÷ 8 = 12.5, rounded up to 13 sections, plus one end post.

      How many pickets do I need for 100 feet of privacy fence?

      219 pickets that are 5½ in wide with no gap: 1,200 in ÷ 5.5 in = 218.2, rounded up.

      How many pickets per foot of fence?

      About 2.2 per foot for 5½ in pickets set tight, or 2 per foot for 3½ in pickets with a 2½ in gap.

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