Rhombus Calculator

A rhombus is a four-sided shape with all sides the same length, like a square that has been pushed over to one side, and it turns up everywhere from tile patterns and kite designs to jewellery, logos and engineering drawings. This calculator works out everything you usually need to know about one from just its two diagonals: the area enclosed, the length of each equal side, and the perimeter all the way around. The diagonals are the lines joining opposite corners, and in a rhombus they have a special property that makes the maths neat, they cross exactly in the middle and meet at right angles. That means each side is simply the long edge of a right-angled triangle whose two short sides are half of each diagonal, so the calculator can find the side using Pythagoras and then the perimeter by multiplying by four. The area is even simpler: half the product of the two diagonals. Enter your diagonals in whatever unit you like, millimetres, centimetres or metres, and all three results appear instantly, in the matching square units for the area. This makes the tool handy for a tradesperson setting out a diamond tile layout, a student tackling geometry homework, a craftsperson planning a quilt or stained-glass panel, or anyone who needs quick, accurate figures for a rhombus without juggling formulas by hand. Because it recalculates the moment you change a value, you can experiment and see how stretching one diagonal changes the side and area. The formulas and a clear worked example are set out below so you can check the method and apply it yourself.