Online Denominator Calculator

Find the lowest common denominator (LCD) of two fractions — the LCM of the two denominators.

First denominator

Second denominator

Common Denominator Calculator

Enter two denominators to get their lowest common denominator (LCD), i.e. the least common multiple (LCM). For example, denominators 4 and 6 give LCD = 12, so 1/4 = 3/12 and 1/6 = 2/12.

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