長方形、正方形、円、三角形、台形、平行四辺形の面積を即座に計算します。公式を覚える必要なし — 数値を入力するだけで結果を確認。純クライアントサイド。
Rectangle: length × width
Circle: π × radius²
Triangle: ½ × base × height
この面積計算機は、6つの一般的な図形の面積と周囲長を計算するのに役立ちます。各図形に対して正しい公式を自動的に使用し、結果を即座に表示します。建築、工芸、学校の課題など、任意のシーンで使用できます。すべての計算はブラウザ内で実行されます。
This calculator supports 8 common geometric shapes: Rectangle, Square, Circle, Triangle, Trapezoid, Parallelogram, Rhombus, and Ellipse. Each shape requires specific measurements to calculate both area and perimeter.
Yes, the area calculator is completely free to use. No registration, no ads, and no limits. All calculations happen in your browser — no data is sent to any server.
Yes, you can choose between centimeters (cm), meters (m), inches (in), and feet (ft). The calculator automatically converts the results to the corresponding area units (cm², m², in², ft²).
Yes, after calculating, the formula used is displayed in a formula box below the results. This helps you understand the math behind the calculation and is useful for learning and verification.
Area measures the space inside a shape (in square units), while perimeter measures the total length of the shape's boundary (in linear units). This calculator provides both values for all supported shapes.
This calculator focuses on standard geometric shapes. For irregular shapes, you can break them down into simpler shapes (like rectangles and triangles), calculate each area separately, and then sum them up.
Yes, the calculator uses standard mathematical formulas and provides results with up to 4 decimal places for precision. For engineering or critical applications, always verify with additional methods.
Absolutely. The calculator is fully responsive and works seamlessly on smartphones, tablets, and desktop computers.