Area Calculator

Enter dimensions in the linear unit for (e.g. meters).

50 m²
UnitArea
50
cm²500000
ft²538.195521
in²77500.155

A = length × width

Area Formulas for Common Shapes

Area measures the amount of two-dimensional surface enclosed by a shape, expressed in square units such as m², cm², ft², or in². Different shapes require different formulas based on their geometry. This calculator provides nine shape tabs, each with the appropriate inputs and formula displayed below the tool.

For a rectangle, A = length × width. A triangle can be found from base and height (A = ½bh) or from three sides via Heron's formula when height is unknown. A circle uses A = πr². A trapezoid with parallel sides a and b and height h has A = ½(a+b)h. An ellipse with semi-axes a and b has A = πab.

A parallelogram follows A = base × height (perpendicular height, not slant side). A rhombus uses its diagonals: A = ½d₁d₂. A regular n-gon with side s has A = ¼ns²·cot(π/n). A circular sector with radius r and angle θ° has A = (θ/360)πr².

Results are computed in square meters internally and converted to your chosen display unit. Toggle between metric (m², cm²) and imperial (ft², in²) using the unit selector. A table shows the equivalent area in all four units for easy comparison.

Each shape includes a schematic SVG diagram. Enter the dimensions for your selected shape and the calculator returns the area instantly with the formula shown for reference.

Examples

ExampleResult
Rectangle 10 × 550 sq units
Triangle b=8, h=6Area = 24
Circle r=3A ≈ 28.27
Trapezoid a=4, b=8, h=5A = 30

Frequently asked questions

Use base × height when you know the altitude. Use three sides (Heron) when you only know side lengths.

Yes. Enter the two semi-axis lengths a and b, not the full widths.

Yes. Choose m², cm², ft², or in²; all conversions are shown in the results table.

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