Siding Calculator

Calculate siding squares for exterior walls.

SQUARES NEEDED
squares
siding squares

Usage Tip

1 square = 100 sq ft. Subtract large openings like windows and doors from the wall area.

THE MATH
Squares = Area × (1 + waste) ÷ 100
Where: 1 square = 100 sq ft
• Subtract major openings (windows, doors)
• Order 10% extra for cuts and matching
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The calculators and tools on Formula Factory are provided for general guidance and informational purposes only. Results are estimates based on standard formulas and the values you enter — they do not constitute professional engineering, electrical, or architectural advice. Always verify calculations with a qualified professional before making decisions for any safety-critical, code-compliance, or commercial application. Formula Factory makes no representations or warranties as to the accuracy or completeness of any result, and accepts no liability for errors, omissions, or any outcomes arising from reliance on this information.