Structure
14 posts
Fence posts
Use the post count as a starting point, then confirm post length for your fence height plus the buried depth and any corner or gate posts.
Fence calculator
Fence calculator for posts, pickets, and rails.
Enter fence length, post spacing, picket width, and gap to estimate posts, rails, and pickets. A 100 ft run at 8 ft spacing needs about 14 posts and 209 pickets.
100 ft at 8 ft spacing
14 posts
209 pickets
Sections
13
26 rails total
Post spacing
8 ft
typical wood fence
Quick fence answers
Common fence lengths
50 ft side yard
8 posts
about 105 pickets
100 ft backyard
14 posts
about 209 pickets
150 ft yard
20 posts
about 314 pickets
Posts need concrete
Most fence posts are set in concrete. Take the post count here into the post-hole calculator with your hole diameter and depth for bags of concrete.
Shopping list
Posts, pickets, rails, and gates
Post and picket counts update from the calculator. Confirm post length, board size, and gate hardware before ordering.
Infill
209 pickets
Pickets or panels
The picket count assumes the entered width and gap. Pre-built panels cover a section at a time and change how you buy.
Rails and base
Rails, concrete, and hardware
Plan rails per section, fast-setting concrete for the post holes, screws, brackets, and any post caps.
Access
Gates and hardware
Gates, hinges, latches, and gate posts are separate from the run length and often the trickiest part of the order.
Formula shown
How the fence estimate works
1. Sections and posts
sections = ceil(length / spacing); posts = sections + 1
2. Rails
rails = sections x rails per section
3. Pickets
pickets = ceil(length x 12 / (picket width + gap))
Straight-run assumption
The post count assumes one continuous straight run. Every corner, gate, and end adds posts, and panels or pre-built sections change how pickets are bought. Add posts for each gate and corner.
Sources
- Fence layout practice — post spacing, rails, and picket layout norms
- Lumber dimensions reference — nominal vs actual picket widths
Reviewed for estimating accuracy
Last updated: June 25, 2026
Estimate only.
This calculator is not a quote. Verify product yield, price, delivery minimums, and local conditions with your supplier or contractor before buying materials.
FAQ
Fence calculator questions
Posts, pickets, post spacing, and concrete for fence posts.
How many fence posts do I need? + -
Divide the fence length by the post spacing (commonly 8 ft) and add one closing post. A 100 ft straight run at 8 ft spacing needs about 14 posts before adding corner and gate posts.
How many pickets do I need for a fence? + -
Pickets depend on width and gap. For 100 ft of fence with 5.5 in pickets and a 0.25 in gap, that is about 209 pickets. Wider boards or larger gaps reduce the count; a butted privacy fence uses the most.
How far apart should fence posts be? + -
Wood fence posts are commonly set 6 to 8 ft apart. Closer spacing is stronger and uses more posts; 8 ft is a typical maximum for a standard wood fence. Match the spacing to your rail length and local wind.
How much concrete do I need for fence posts? + -
That depends on the hole diameter and depth, not the fence length. Estimate it with the post-hole concrete calculator using your post count, hole size, and depth.