Geometry & Science

Area Calculator

Calculate area for a rectangle, triangle, circle or trapezoid from the dimensions you enter.

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Geometry & Science

Geometry, statistics and practical science formulas.

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How to use this area calculator

Enter the requested values above and select Calculate. Change the inputs to compare scenarios.

Formula and method

Rectangle: A = length × width. Triangle: A = ½ × base × height. Circle: A = πr². Trapezoid: A = ½ × (b₁ + b₂) × h.

Example

Choose a shape, enter its dimensions, and the calculator returns the area in square units.

What this calculator is useful for

Calculate area for a rectangle, triangle, circle or trapezoid from the dimensions you enter.

Frequently asked questions

What does this calculator do?

Calculate area for a rectangle, triangle, circle or trapezoid from the dimensions you enter.

What data or formula does it use?

Uses standard Euclidean geometry formulas. Units are generic, so keep all dimensions in the same unit.

Is it free?

Yes. ERICH Calculators is free to use and no account is required.

Source & assumptions

Reference and limitation

Uses standard Euclidean geometry formulas. Units are generic, so keep all dimensions in the same unit.

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Method, assumptions & corrections

See how formulas, sources and limitations are handled across ERICH Calculators.