justyourcalculatorArea Calculator
Pick a shape, enter its sizes, and get the area with the formula shown.
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Area Calculator
Area of rectangles, triangles, circles and more
Area
40 m²
- Perimeter
- 26 m
- Diagonal
- 9.43398113 m
How it was calculated
- A = length × width
- A = 8 × 5 = 40 m²
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How the area calculator works
Area is the amount of flat space inside a shape, measured in square units (m², ft², and so on). Rectangle: length × width. Parallelogram: base × perpendicular height. Triangle: half of base × height, or Heron's formula when you know all three sides.
Trapezoid: the average of the two parallel sides times the height. Circle: π × r². A sector (a pizza slice) is the fraction of the circle its angle covers: θ / 360° × π r². Ellipse: π × a × b, using the two semi-axes.
Every result is in the square of the unit you choose. To convert, square the length factor: 1 m² = 10.764 ft², and 1 ft² = 144 in².
Using and checking your result
Published by JustYourCalculator. Check the units and assumptions above, and compare a known example before relying on the output. Calculations use browser arithmetic and may round displayed values.
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