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Picket Fence Calculator

Enter the length of your fence, the picket width and the gap you want between pickets. The calculator counts pickets, posts, rails and fasteners, subtracts gate openings and adds spare pickets for splits and cuts.

Enter your measurements

Measurements
ft

Measure along the fence line, including any gate openings.

ft

Pickets are not counted across gate openings. Gates themselves are bought or built separately.

in

A nominal 1×4 picket is about 3.5 in (89 mm) wide.

in

Traditional picket fences often use gaps of about 1½–3 in (40–75 mm). Pool fences have strict maximum gaps; check local rules.

ft

8 ft (2.4 m) is common because rails are sold in that length. Shorter spacing makes a stiffer fence.

Material & assumptions
%

Spare pickets for splits, knots and cuts at posts and ends.

Enter your measurements and press Calculate to see quantities, a material breakdown and an optional cost estimate.

How the calculation works

  • Pickets = (Fence length − Gates + Gap) ÷ (Picket width + Gap), rounded up
  • Sections = Fence length ÷ Post spacing, rounded up
  • Posts = Sections + 1
  • Rails = Sections × Rails per section

Each picket takes up its own width plus one gap. Adding one gap to the length accounts for having one fewer gap than pickets on a run.

Posts are counted for a single straight run. Corners and gates usually need extra or heavier posts.

Assumptions used

  • Pickets are counted across the full run between gates, ignoring the small width taken by posts. This builds in a few spare pickets.
  • Fastener count assumes two nails or screws per picket at each rail.

Example calculation

A 100 ft fence with one 4 ft gate, 3.5 in pickets, 2.5 in gaps, posts every 8 ft and 2 rails, with 5% spare pickets.

  1. 1Picket run: 100 − 4 = 96 ft = 1,152 in
  2. 2Pickets: (1,152 + 2.5) ÷ (3.5 + 2.5) = 192.4, so 193
  3. 3With 5% spare: 203 pickets
  4. 4Sections: 100 ÷ 8 = 12.5, so 13; posts: 14; rails: 26

Result: 203 pickets, 14 posts and 26 rails.

How to measure your project

  • Mark the fence line with string and measure its full length, including gates.
  • Measure an actual picket. Nominal 1×4 pickets are usually about 3.5 in (89 mm) wide.
  • Check property lines and any local height or setback rules before you buy.

Frequently asked questions

How far apart should pickets be?

Traditional picket fences often use gaps of about 1½–3 in (40–75 mm), roughly half to one picket width. Pool fences and some local codes set a maximum gap, so check the rules that apply to you.

How many pickets are in an 8 ft section?

With 3.5 in pickets and 2.5 in gaps, each picket takes 6 in, so an 8 ft (96 in) section holds about 16 pickets. Narrower gaps need more.

How deep should fence posts be set?

A common guide is about one-third of the post's above-ground height, and below the frost line where the ground freezes. Use the fence post concrete calculator to work out concrete for the holes.

Related guides

  • Cross-section illustration of fence posts set in concrete-filled holes with a gravel base
    Concrete

    How to Calculate Concrete for Fence Posts

    Calculate how much concrete you need per fence post, including hole size, post displacement and gravel base, with examples for 4×4 and 6×6 posts.

    3 min read

Results are estimates based on the measurements and assumptions you enter. Always confirm product specifications, local building codes and final quantities with your supplier or a qualified professional. See our disclaimer.