Rhombus Calculator
Calculate area, side length, perimeter, and angles of a rhombus from its diagonals.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
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Request a ToolHow to Use the Rhombus Calculator
Enter the lengths of both diagonals and the calculator computes the area, side length, perimeter, and interior angles.
- Enter diagonal 1 (p). The length of the first diagonal.
- Enter diagonal 2 (q). The length of the second diagonal.
- Read the results. Area is the primary result. Side length, perimeter, and angles appear below.
Area = (p * q) / 2. Side = sqrt((p/2)^2 + (q/2)^2). Perimeter = 4 * side.
About Rhombuses
A rhombus is a quadrilateral with all four sides equal in length (an equilateral quadrilateral). Its diagonals bisect each other at right angles. The area equals half the product of the diagonals. A square is a special rhombus where all angles are 90 degrees. Rhombuses appear in diamond patterns, tilework, and kite designs. They are also a special case of parallelogram, so opposite angles are equal.
Frequently Asked Questions
What is the area of a rhombus?
Area = (d1 * d2) / 2, where d1 and d2 are the lengths of the two diagonals. For diagonals of 10 and 8, the area is 40.
How do you find the side length of a rhombus from its diagonals?
Since the diagonals bisect each other at right angles, each side is the hypotenuse of a right triangle with legs d1/2 and d2/2. So side = sqrt((d1/2)^2 + (d2/2)^2).
Is a square a rhombus?
Yes. A square is a rhombus where all angles are 90 degrees. It is also a rectangle. This makes it both a rhombus and a rectangle simultaneously.