Rectangle Calculator
Find rectangle area, perimeter, diagonal, and aspect ratio from two side lengths.
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How to use Rectangle Calculator
A rectangle has area length × width, perimeter 2(length + width), and diagonal √(length² + width²). The aspect ratio is length divided by width.
- Enter length, width.
- Check that the input follows the stated limits and uses consistent units.
- Run the calculator, review the result, then copy or download it.
Good to know
- Both side lengths must be positive and use the same unit. This assumes right angles.
- Decimal inputs have at most 120 characters and magnitude from 1e-100 to 1e15, or zero. Floating-point results are rounded to 12 significant digits; extreme derived results may underflow or be rejected. Exact integer results are identified separately.
Common questions
What calculation does Rectangle Calculator perform?
A rectangle has area length × width, perimeter 2(length + width), and diagonal √(length² + width²). The aspect ratio is length divided by width.
Can I use this for an irregular quadrilateral?
No. Two lengths are sufficient only when the shape is a rectangle with four right angles.
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