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CalculatorGe

床面積計算機

Calculate the square footage (or square meters) of rooms, floors, yards and lots in rectangular, L-shaped, circular, triangular or trapezoid shapes, and estimate material cost.

計画用の概算です。ロス分を見込み、地域の建築・電気の規定に従い、構造や電気の工事は有資格の専門家に確認してもらってください。

以下のガイドはまだ日本語に翻訳されていないため、英語で表示しています。計算機自体はすべて日本語に対応しています。

この計算機の使い方

  1. Choose units and the shape that matches the space. Split complex rooms into several shapes and add them up.
  2. Enter the dimensions.
  3. Optionally enter a price per square foot or square meter to estimate cost.

計算式

Square footage is an area measurement. Measure in feet; for feet-and-inches measurements, convert inches to decimal feet first (inches ÷ 12).

Rectangle: L × W
L-shape: (L₁ × W₁) + (L₂ × W₂)
Circle: π × (D/2)²
1 m² = 10.7639 ft²; 1 yd² = 9 ft²

Example

  1. A 12 ft × 10 ft room = 120 ft² = 11.15 m².
  2. At $4.50/ft² for flooring: 120 × 4.50 = $540 before waste.

よくある質問

How do I convert 10 ft 6 in to decimal feet?

6 in ÷ 12 = 0.5, so 10 ft 6 in = 10.5 ft.

Should I add extra for flooring?

Yes. Add 5–10% for straight layouts and 10–15% for diagonal or patterned layouts to cover cuts and waste. The tile calculator includes a waste setting.

Does home square footage include walls?

Real-estate measurement standards (such as ANSI Z765 in the US) measure finished area to exterior walls. Rules vary by country.