This fence calculator works out your materials list — posts, rails and pickets — from the fence length, post spacing and picket dimensions, for a standard wood privacy fence.
Posts = sections + 1 per continuous run — if your fence has separate runs or corners, add one post per extra run and one per gate. Figures assume pickets cover a single side; board-on-board styles need about 25–30% more pickets.
How Fence Estimating Works
A fence is a repeating section — post, rails, pickets — so the materials list is arithmetic: divide length by spacing for sections (round up), add a post, multiply sections by rails, and cover the run with pickets at (picket width + gap) each. Lumber quantities in general can be cross-checked with the Board Foot Calculator; this tool is part of our Construction Calculators collection.
Worked Example (Verified)
A 100 ft fence, 8 ft post spacing, 2 rails, 5.5″ pickets with ½″ gaps:
- Sections: 100 ÷ 8 = 12.5 → 13 sections
- Posts: 13 + 1 = 14 posts
- Rails: 13 × 2 = 26 rails
- Pickets: each covers 6 inches → 100 × 2 = 200 pickets (order ~220 — pickets are the most breakage- and defect-prone item on the list)
Planning Notes the Calculator Can’t See
- Gates need their own framing, hinges and usually a post on each side — budget them separately (a 4 ft gate opening fits inside one section’s pickets).
- Post depth: the rule of thumb is one-third of the post underground, below the frost line — an 8 ft post for a 6 ft fence, set ~2 ft deep in concrete (about one 60 lb bag per post, two for corner/gate posts).
- Corners and ends each consume a post — the per-run +1 in the note above. Measure each straight run separately for odd-shaped yards and add the results.
- Order 10% extra pickets and rails — lumber defects show up on install day, not at the store.
Related Tools
- Board Foot Calculator — lumber volumes and cost
- Construction Calculators — the full collection
Frequently Asked Questions
How many fence posts do I need for 100 feet?
At 8 ft spacing: 13 sections + 1 = 14 posts for one straight run. At 6 ft spacing: 17 sections + 1 = 18.
How many pickets do I need per foot?
With 5.5″ pickets and a ½″ gap, each picket covers 6 inches — 2 pickets per foot. No-gap privacy style (5.5″ coverage): about 2.2 per foot.
How far apart should fence posts be?
Eight feet is the residential standard for wood privacy fences; 6 ft is sturdier for tall fences, windy sites, or heavy board-on-board styles.
How much concrete per fence post?
Roughly one 50–60 lb bag per standard post hole, more for corner, end and gate posts. The hole should be about 3× the post width.
Does this calculator handle board-on-board fences?
The picket count covers a single layer with gaps. Board-on-board overlaps pickets with no gaps — add 25–30% more pickets to the result.
Is this fence calculator free?
Yes — free, instant, no sign-up.