Rectangle Fence Perimeter Calculator

Enter your rectangle's dimensions to get the fence length, area, diagonal and suggested post count. Units supported: ft, m, yd, cm.

Results

Fence Perimeter
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P = 2 × (L + W) - G
Area
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A = L × W
Diagonal
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D = √(L² + W²)
Rectangle fence diagram showing length, width, and gate opening Length (L) Width (W)

Frequently Asked Questions

How do I measure my yard for a fence?

Measure the length and width of your rectangular area at ground level. For irregular shapes, break it down into rectangles. Measure from the center points where posts will be placed for accuracy.

Do I subtract gate openings from the perimeter?

Yes, gate openings are subtracted from the total fence length since you won't need fencing material for those sections. Our calculator does this automatically when you provide the gate width.

How much spacing should I leave between fence posts?

Standard post spacing is 6-8 feet for wood fences and 8-10 feet for vinyl fences. Closer spacing provides more stability but increases cost. Check local building codes for requirements.

Fence Installation Best Practices

When planning your fence project, always check local zoning laws and property lines before installation. Contact utility companies to mark underground lines. For accurate measurements, use a measuring tape and consider using stakes and string to outline the fence perimeter. Add 5-10% to material estimates for waste and errors.

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