About This Calculator

1. What is this calculator for?
2. Can I embed this on my website?
3. How do I find the least common multiple by hand?

What is this calculator for?

This calculator finds the least common multiple (LCM) of a set of integers. It can be used to find it for two or more numbers.

Can I embed this on my website?

Sure. Embedding is allowed as long as you promise to follow our conditions. Here's the embed code:

<iframe width="415" height="220" src="http://www.a-calculator.com/lcm/embed.html" frameborder="0" allowtransparency="true"></iframe>

How do I find the least common multiple by hand?

Here's an example. To find the least common multiple of 4 and 6 we could list the multiples of each of them:

• The multiples of 4 are 4, 8, 12, 16, 20, 24, 28, 32, 36, 40...
• The multiples of 6 are 6, 12, 18, 24, 30, 36...

Now we can see that 4 and 6 have the divisors 12, 24, 36 (and so on) in common, but 12 is the lowest. Therefore the least common multiple of 4 and 6 is 12.

Another common technique is to use the greatest common divisor \( \def\myfunc{\text{lcm}} \) \begin{equation} \myfunc(a, b) = \frac{|a \times b|}{\gcd(a, b)}. \end{equation} To apply it to three numbers \(a, b\) and \(c\) you can simply use \(\myfunc(a, \myfunc(b, c))\).