How the LCM Calculator Works

When you press Calculate LCM, the tool runs three checks on your numbers and shows each one. Seeing the same answer three ways makes it easy to trust, and easy to learn from.

Prime factorization

Each number is split into primes. For 84 that is 2² × 3 × 7. The LCM takes the highest power of every prime found in any number.

Multiples

The tool lists the multiples of each number up to the LCM. When the lists get long, it shows the first few and then jumps to the answer.

GCD formula

Using the greatest common divisor, the tool applies LCM(a, b) = (a × b) ÷ GCD(a, b). With more than two numbers it works one pair at a time.

Limits and privacy

• Whole numbers from 1 to 1,000,000,000,000.
• Up to 10 numbers at once.
• All math runs in your browser. Nothing you type is sent anywhere.
• Recent calculations are stored in your browser only. Use Clear history to remove them.

Ready to try it? Go to the LCM Calculator.