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CalcVerse

Flächenrechner

Calculate the area (and perimeter where defined) of common shapes: rectangle, square, circle, triangle, trapezoid, parallelogram, ellipse, circular sector and regular polygon.

Die folgende Anleitung ist noch nicht auf Deutsch verfügbar und wird auf Englisch angezeigt. Der Rechner selbst ist vollständig übersetzt.

So verwenden Sie diesen Rechner

  1. Choose a shape.
  2. Enter its dimensions in any consistent unit (all in cm, or all in feet, for example).
  3. The area is in square units of what you entered.

Formel

Each shape has its own formula.

Rectangle: A = l × w
Circle: A = πr², C = 2πr
Triangle: A = ½ × b × h
Trapezoid: A = ½(a + b) × h
Ellipse: A = πab
Sector: A = (θ/360) × πr²
Regular n-gon: A = n s² / (4 tan(π/n))

Example

  1. Circle with radius 3: A = π × 9 ≈ 28.274 square units.
  2. Circumference = 2π × 3 ≈ 18.850 units.

Häufige Fragen

How do I find the area of an irregular shape?

Split it into rectangles, triangles and circles, calculate each area, and add them together (or subtract cut-outs).

How do I convert square feet to square meters?

1 square foot = 0.09290304 m². Use the area converter for any area units.

Why is the ellipse perimeter approximate?

An ellipse's perimeter has no simple exact formula. Ramanujan's approximation used here is accurate to within a tiny fraction of a percent.