面積計算機

共有リンク

はじめに

Area Calculator — Calculate area for rectangles, triangles, and circles. Enter Shape, A (length / base / radius), B (width / height) to get an instant, accurate result.

計算式

Rectangle: area = a×b. Triangle: area = ½×a×b (base × height). Circle: area = π×a² (a as radius).

ステップごとの説明

Enter the Shape.
Enter the A (length / base / radius).
Enter the B (width / height).
Click Calculate to see your result instantly.

実例

Example: With Shape = rectangle, A (length / base / radius) = 4, B (width / height) = 5, the Area Calculator gives Area: 20.

よくある質問

Which shapes are supported?

Rectangle, triangle, and circle.

For a triangle, what do a and b represent?

Base and height, not two arbitrary sides.

What inputs does the Area Calculator need?

You'll need to provide: Shape, A (length / base / radius), B (width / height). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.

How accurate is the Area Calculator?

The Area Calculator applies the formula exactly as calculated — Rectangle: area = a×b. Triangle: area = ½×a×b (base × height). Circle: area = π×a² (a as radius). — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.

Is the Area Calculator free to use?

Yes, the Area Calculator is completely free, requires no signup, and runs instantly in your browser.