Area Calculator " Square, Rectangle, Circle, Triangle

Q: What is the difference between area and perimeter?

Area measures the space inside a two-dimensional shape, while perimeter measures the length of the outside boundary.

Q: How many square feet are in an acre?

One acre is exactly equal to 43,560 square feet.

Select Shape:

What is an Area Calculator?

An area calculator is a tool that computes the total surface area of geometric shapes like squares, rectangles, circles, triangles, and polygons. It's essential for construction, landscaping, interior design, and math homework.

Common Area Formulas

Rectangle/Square: Area = Length × Width
Circle: Area = π × Radius²
Triangle: Area = 0.5 × Base × Height
Trapezoid: Area = 0.5 × (Base 1 + Base 2) × Height

How to Use This Calculator

Select the shape: Choose from the drop-down menu (e.g., Circle, Rectangle).
Enter dimensions: Input the required measurements like radius, base, or height.
Click Calculate: Get the exact area instantly in your preferred unit (sq ft, sq m, acres, etc.).

Real-World Example

If you are painting a rectangular wall that is 12 feet long and 8 feet high, the area is 12 × 8 = 96 square feet. If one gallon of paint covers 400 sq ft, you know one gallon is more than enough.

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Frequently Asked Questions

How do I calculate the area of an irregular shape?

Break the irregular shape down into simpler geometric shapes like rectangles and triangles. Calculate the area of each part individually, then add them together.

What is the difference between area and perimeter?

Area measures the space inside a two-dimensional shape (measured in square units), while perimeter measures the total length of the outside boundary of the shape.

How many square feet are in an acre?

One acre is equal to 43,560 square feet. This is useful when measuring land or large properties.