Rhombus Area Calculator

Use $A = \frac{d_1 \times d_2}{2}$, where $d_1$ and $d_2$ are the two diagonals. Alternatively, use $A = s^2 \times \sin(\theta)$, where $s$ is the side length and $\theta$ is any interior angle.

They are the same shape. “Diamond” is the informal name for a rhombus — a quadrilateral with all four sides equal. A rhombus has two pairs of equal opposite angles and perpendicular diagonals.

Yes. A square is a rhombus where all angles are $90^\circ$. Since $\sin(90^\circ) = 1$, the area formula simplifies to $A = s^2$. The diagonals of a square are equal: $d_1 = d_2 = s\sqrt{2}$.

Because a rhombus is a parallelogram with equal sides, the diagonals bisect each other. The equal side lengths force the four resulting triangles to be congruent right triangles, making the diagonals perpendicular.

Use the Pythagorean theorem on the half-diagonals: $s = \sqrt{\left(\frac{d_1}{2}\right)^2 + \left(\frac{d_2}{2}\right)^2}$. Since the diagonals bisect each other at right angles, each side is the hypotenuse of a right triangle formed by half of each diagonal.