Fence calculator
Estimate how many pickets, posts and rails a fence project needs, including gates.
Fence calculator
Estimate how many pickets, posts and rails a fence project needs, including gates.
Enter your fence dimensions to see the material estimate.
Pickets needed
Project summary
How it works
These are material estimates, not structural specifications. Check local building codes and property boundaries before building.
Fence calculator
Posts are the most expensive mistake to get wrong
A fence stands or falls on its posts. Post spacing determines how many sections the fence has, and each section needs a post at each end. Getting the count right matters because adding a post later means digging into a finished fence line. The calculator works the post count from the spacing you choose, including separate posts for each gate.
Picket count depends on the gap
The number of pickets per section is driven by the picket width plus the gap between them, not by the section width alone. A wider picket with a smaller gap needs fewer pickets per foot of fence. The calculator divides the section width by the combined width of one picket plus one gap and rounds up, which is the correct way to count them.
Rails connect everything together
Rails run horizontally between posts and carry the pickets. A standard fence uses two rails for shorter heights and three rails for taller fences. The calculator lets you choose and multiplies the number of rails per section by the number of sections to get the total.
Frequently asked questions
How many fence posts do I need for 100 feet of fence?
At 8 foot post spacing, 100 feet of fence needs 14 posts (one at each end and one at each section boundary). Add two posts for each gate. The calculator above works this out from your actual spacing and gate count.
How do I calculate fence pickets?
Divide the section width by the picket width plus the gap between pickets, then round up. For a 8 foot section with 5.5 inch pickets and 3/8 inch gaps, that is 96 inches divided by 5.875 inches, which gives about 17 pickets per section. Multiply by the number of sections and add the waste allowance.
How many fence pickets do I need for 100 feet?
With standard 5.5 inch wide pickets and a 3/8 inch gap, you need about 206 pickets for 100 feet of fence. The calculator gives you the exact count based on your picket width and the gap you select. It also adds a waste percentage for cuts and damaged boards.
How far apart should fence posts be?
Most residential fences use 8 foot post spacing, which is the maximum allowed by most building codes for standard wood fencing. 6 foot spacing is stronger and better for privacy fences in windy areas. The calculator lets you enter any spacing from 4 to 12 feet and adjusts the post count accordingly.
Do I need a permit to build a fence?
Many municipalities require a fence permit, especially for fences over 6 feet or those in front yards. Some HOAs have additional restrictions on height, material and colour. Check with your local building department and your HOA if you have one before starting. The calculator helps you estimate materials for your permit application.
What is the cheapest fence to build?
A simple privacy fence with pressure treated pine pickets and posts is usually the most affordable option. Chain link is cheaper but offers no privacy. The calculator estimates material quantities for wood fencing, and you can compare the total against chain link or vinyl quotes from local suppliers.
How long does a wood fence last?
A pressure treated wood fence typically lasts 15 to 20 years. Cedar and redwood last 20 to 25 years with proper maintenance. Regular staining or sealing every two to three years extends the life significantly. The calculator helps you budget for the initial material cost, and you can plan for replacement by noting the expected lifespan.
How many rails do I need for my fence?
A standard fence uses two rails for heights up to 6 feet and three rails for taller fences. The calculator multiplies the number of rails per section by the number of sections to get the total. For a 100 foot fence at 8 foot post spacing with two rails per section, that is 26 rails before waste.