Fence Calculator
Use this fence calculator to estimate panels, posts, and pickets for a new fence or a replacement section. Enter the fence length and spacing values to get a quick material estimate before you order lumber or hardware.
Result
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What This Fence Calculator Helps You Do
Use this fence calculator to estimate panels, posts, and pickets for a new fence or a replacement section. Enter the fence length and spacing values to get a quick material estimate before you order lumber or hardware.
How to Calculate Fence Calculator
- Measure the fence run - Enter the total fence length in feet. Break the project into sections if the layout changes direction.
- Enter spacing details - Set the panel width or post spacing, then choose picket width and gap if you want a picket estimate.
- Add waste allowance - Waste helps cover cuts, damaged boards, and short adjustments during installation.
- Review the counts - Use the output as a planning estimate and round up before you buy materials.
Fence Calculator Formula
| Symbol | Definition | Unit |
|---|---|---|
| Length | Fence run length | ft |
| Panel width | Width of one fence section | ft |
| Post spacing | Distance between fence posts | ft |
| Picket width | Width of one picket | ft |
| Picket gap | Space between pickets | ft |
Worked Examples
- Length: 100 ft
- Panel width: 8 ft
- Post spacing: 8 ft
- Waste: 10%
Result: Panels = 12.5. Posts = 13.5.
A 100-foot run comes out to about 12.5 panels and 13.5 posts before waste.
- Length: 60 ft
- Panel width: 6 ft
- Post spacing: 6 ft
- Waste: 8%
Result: Panels = 10. Posts = 11.
A shorter fence run produces a clean round number of panels and posts.
- Length: 80 ft
- Picket width: 0.5 ft
- Picket gap: 0.25 ft
- Waste: 12%
Result: Pickets = 133.33.
The picket count rises quickly because the visible board plus gap repeats across the whole run.
- Length: 150 ft
- Panel width: 8 ft
- Post spacing: 8 ft
- Waste: 10%
Result: Panels = 18.75. Posts = 19.75.
A longer perimeter needs many sections, so it is worth checking waste and corner details carefully.
How to Interpret Your Results
| Range | Meaning | Action |
|---|---|---|
| < 10 panels | Small fence run | A single material order may be enough. |
| 10-20 panels | Typical backyard fence | Check post layout and confirm your gate openings. |
| 20-40 panels | Large fence project | Review delivery timing and compare section styles. |
| > 40 panels | Very large perimeter | Break the job into segments and verify corner and gate counts. |
Frequently Asked Questions
Sources
Last reviewed: March 2026