Area Calculator – Calculate Area of Any Shape
The area calculator instantly computes the area of common 2D shapes including rectangles, circles, triangles, trapezoids, ellipses, parallelograms, rhombuses, and squares. Simply select your shape, enter the required dimensions, and get an accurate area result with the formula used. Whether you're working on a home improvement project, school assignment, or engineering task, this tool makes area calculations fast and effortless.
Select the shape you want to calculate the area for.
Enter the primary dimension: length (rectangle/parallelogram), base (triangle/trapezoid), radius (circle), semi-major axis (ellipse), side or diagonal a (rhombus), or side (square).
Enter the secondary dimension where applicable: width (rectangle), height (triangle/trapezoid/parallelogram), semi-minor axis (ellipse), or second diagonal (rhombus). Leave blank for circle or square.
For trapezoids only: enter the length of the top (parallel) base.
Your results will appear here
How to Use This Calculator
1. Select the shape you want to calculate from the Shape dropdown menu. 2. Enter the required dimensions in the fields provided — for example, length and width for a rectangle, or radius for a circle. 3. For a trapezoid, also fill in the Top Base field. 4. Choose your unit of measurement (meters, feet, inches, etc.). 5. Click Calculate to instantly see the area, its unit squared, and the formula that was applied.
How Area Is Calculated
Area is the measure of the two-dimensional space enclosed within a shape's boundary. Each shape has its own formula derived from its geometric properties. Below are the formulas used by this calculator:
Rectangle
Area = Length × Width
A rectangle's area is simply the product of its two sides. A square is a special case where both sides are equal, so Area = Side².
Circle
Area = π × r²
Where r is the radius (the distance from the center to the edge) and π ≈ 3.14159. The radius is half the diameter.
Triangle
Area = ½ × Base × Height
The height must be perpendicular to the chosen base. This formula applies to all triangles regardless of type.
Trapezoid
Area = ½ × (Base₁ + Base₂) × Height
A trapezoid has two parallel sides (bases). The area is the average of the two bases multiplied by the height between them.
Ellipse
Area = π × a × b
Where a is the semi-major axis and b is the semi-minor axis. An ellipse is a stretched circle.
Parallelogram
Area = Base × Height
The height is the perpendicular distance between the two parallel bases, not the slant side length.
Rhombus
Area = ½ × d₁ × d₂
Where d₁ and d₂ are the lengths of the two diagonals. A rhombus is a parallelogram with all sides equal.
Common Unit Conversions for Area
- 1 m² = 10,000 cm²
- 1 km² = 1,000,000 m²
- 1 ft² = 144 in²
- 1 yd² = 9 ft²
- 1 acre = 43,560 ft²
- 1 hectare = 10,000 m²
Practical Applications
Area calculations are essential in many real-world scenarios:
- Construction & flooring: Calculating how much tile, carpet, or paint is needed.
- Landscaping: Determining the amount of grass seed, mulch, or fertilizer required.
- Real estate: Measuring the floor area of rooms or properties.
- Agriculture: Estimating field sizes for planting or irrigation planning.
- Education: Solving geometry problems in school or standardized tests.