Math & Statistics · Browser · Free

Ratio Calculator

Type two numbers into the A and B fields and press Calculate to see their ratio written in several equivalent ways. Each result appears in a card below the button.

What the calculator shows

The form has two number fields, A and B, and one Calculate button. Nothing is worked out until you press the button, and every result is shown in cards underneath it. Copy writes a result and its unit to the clipboard, and Clear resets the form.

Each result keeps the ratio you entered and adds other ways of writing the same relationship: a simplified whole-number form, a form with 1 on the left, and a form with 1 on the right. When one of those forms is a rounded decimal, this page writes it as about that value.

Worked example

For A: 1920, B: 1080 the tool returns "Ratio: 1920:1080 = 16:9 = 1:0.5625 ≈ 1.77777777777778:1". The simplified whole-number form is 16:9, the left side becomes 1:0.5625, and the right side becomes about 1.77777777777778:1.

A smaller pair works the same way. For A: 6, B: 4 the tool returns "Ratio: 6:4 = 3:2 ≈ 1:0.666666666666667 = 1.5:1", so the simplified ratio is 3:2, the form with 1 on the left is about 1:0.666666666666667, and the form with 1 on the right is 1.5:1.

Ratio formula

The ratio of A to B is written A:B. The other forms are the same ratio scaled so that one side is 1, which gives A:B = 1 : (B ÷ A) = (A ÷ B) : 1. For A: 4, B: 2 that produces the line "Ratio: 4:2 = 1:0.5 = 2:1".

The simplified form is the same ratio expressed in smaller whole numbers, as with 1920:1080 becoming 16:9. If two of these forms turn out to be the same, the result shows that form once, which is why A: 1, B: 1 comes back simply as "Ratio: 1:1".