Calculate rectangle area, perimeter, diagonal, and dimensions from any two known values with step-by-step solutions.
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Calculate all properties of a rectangle from any two known values. Enter length and width, length and area, length and perimeter, or diagonal and length to get all measurements instantly.
A rectangle is a quadrilateral with four right angles. The key formulas are: Area = length × width, Perimeter = 2(length + width), and Diagonal = √(length² + width²). A square is a special rectangle where length equals width.
Rectangle Area Formula
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A square is a special type of rectangle where all four sides are equal (length = width). All squares are rectangles, but not all rectangles are squares. Our calculator detects when dimensions form a square.
The diagonal of a rectangle can be found using the Pythagorean theorem: d = √(l² + w²), where l is length and w is width. The diagonal connects opposite corners of the rectangle.
Aspect ratio is the proportional relationship between width and height, expressed as two numbers (e.g., 16:9). It's commonly used in displays, photography, and design to describe the shape of rectangular objects.