Area Calculator
Calculate the area of 7 common shapes with full unit conversion — useful for land, rooms, pools, and more.
Rectangle
⚠️ Please enter valid positive numbers for all fields.
Common Area Unit Reference
| Unit | Equivalent in m² | Common Use |
|---|---|---|
| Square Meter (m²) | 1 m² (SI base unit) | Rooms, small plots |
| Square Centimeter (cm²) | 0.0001 m² | Small objects, paper |
| Square Kilometer (km²) | 1,000,000 m² | Cities, countries |
| Square Foot (ft²) | 0.0929 m² | Real estate (US) |
| Square Inch (in²) | 0.000645 m² | Small surfaces |
| Square Yard (yd²) | 0.8361 m² | Carpet, fabric |
| Acre | 4,046.86 m² | Land (US/UK) |
| Hectare (ha) | 10,000 m² | Agriculture, land |
| Square Mile (mi²) | 2,589,988 m² | Large regions |
About Area Calculation
Rectangle & Square
Area = Length × Width. A square is a special rectangle where all sides are equal.
Triangle (Heron's Formula)
Given 3 sides (a, b, c): s = (a+b+c)/2, then Area = √[s(s−a)(s−b)(s−c)].
Trapezoid
Area = ((Base₁ + Base₂) / 2) × Height. Useful for irregular land plots.
Parallelogram
Area = Base × Height (perpendicular height, not slant side).
Circle
Area = π × r². The radius is the distance from the center to any edge point.
Sector (Pie Slice)
A fraction of a circle: Area = (θ / 360°) × π × r² for degrees, or (θ / 2) × r² for radians.
Ellipse
Area = π × a × b, where a = semi-major axis and b = semi-minor axis. A circle is a special ellipse where a = b.