Fence Calculator

Calculate posts, rails, and materials for fence installation

Project Details
Enter your measurements and requirements
Results
Calculated estimates for your project
Total Length0 ft
Posts Needed1
Rails Needed3
Pickets/Panels0

Additional Information

About This Fence Calculator

Our fence calculator helps you determine how many posts, rails, and pickets or panels you need for your fence installation. Whether you're building a privacy fence, picket fence, or ranch-style fence, this tool calculates materials based on your total linear footage and post spacing.

Accurate material estimation prevents mid-project trips to the store and helps you budget correctly. The calculator accounts for the number of posts needed (including end posts) and estimates rails based on standard three-rail construction. Picket counts are based on standard 3.5-inch pickets with spacing.

This tool is designed for DIY homeowners planning fence projects, contractors preparing estimates, and anyone asking "how many posts do I need for 100 feet of fence?" Remember to check local building codes and property lines before installing a fence.

How to Use This Calculator

Follow these steps to calculate your fence materials:

  1. Measure the total linear feet of fence needed
  2. Enter the desired fence height in feet
  3. Specify post spacing (typically 6-8 feet between posts)
  4. Review the number of posts, rails, and pickets needed
  5. Add 5-10% extra for waste and irregular terrain
Frequently Asked Questions

How much does it cost to build a fence?

Wood privacy fence costs $15-35 per linear foot installed, or $8-15 per foot for DIY materials only. A typical 150 linear foot fence costs $1,200-2,250 in materials. Cedar costs more than pressure-treated pine but lasts longer. Vinyl and composite fencing cost $20-40 per foot but require less maintenance.

How far apart should fence posts be?

Standard post spacing is 6-8 feet for most fence types. Use 6-foot spacing for areas with high winds or heavy privacy panels. Use 8-foot spacing for lighter fence styles or sheltered areas. Posts should never be more than 8 feet apart or rails may sag. Corner and gate posts need closer adjacent posts for support.

How deep should fence posts be?

Bury fence posts 1/3 of their total length - for a 6-foot fence with 8-foot posts, bury 2.5 feet deep. Minimum depth is 24 inches, but deeper is better for stability and frost heave prevention. In cold climates, extend below the frost line. Use gravel at the bottom for drainage and concrete around the post for stability.

Do I need a permit to build a fence?

Most jurisdictions require permits for fences over a certain height (often 6 feet). HOAs often have additional restrictions on fence style, height, and materials. Always check local building codes, HOA rules, and property setback requirements. Call 811 before digging to locate underground utilities.

Should I use wood or vinyl fencing?

Wood fencing costs less upfront but requires staining or painting every 2-3 years and may rot or warp. Vinyl costs 2-3 times more but never needs painting and won't rot. Vinyl can crack in extreme cold and fade in sun. Consider your climate, budget, and willingness to maintain when choosing.

How long do fence posts last?

Pressure-treated pine posts last 10-15 years in ground contact. Cedar posts last 15-20 years. Using gravel drainage and proper installation extends life. Metal post brackets keep wood out of ground contact for much longer life but cost more. Consider post sleeves or concrete collars to protect the critical ground-level zone.

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