How the fence calculator works
Sections = fence length ÷ post spacing (rounded up) · Posts = sections + 1
Pickets = fence length (in) ÷ (picket width + gap)
Concrete assumes 4 × 4 posts (3.5 in actual) in round holes, with 80 lb bags yielding 0.6 cubic feet each.
Example: 100 ft of 6 ft privacy fence
With posts every 8 feet you get 13 sections and 14 posts. Three rails per section is 39 rails. Pickets 5.5 inches wide with no gap take 1,200 ÷ 5.5 = 218.2, so 219 pickets. Setting each post in a 10 inch hole 2 feet deep takes 22 bags of 80 lb concrete.
Before you dig
Call 811 a few days ahead so underground utilities are marked, check your property line, and ask about local height limits and permits.
Frequently asked questions
How far apart should fence posts be?
Six to eight feet. Eight feet suits standard 8 ft rails; closer spacing makes a stronger fence in windy areas.
How deep should fence posts be?
A common rule is one third to one half of the above-ground height, and below the frost line in cold climates.
Does this include gates?
No. Subtract the gate width from the fence length and add two sturdy gate posts for each gate.
Last reviewed: 2026-10-31