LCM and GCF Calculator
Last updated: July 2026
Find the greatest common factor and least common multiple of two whole numbers.
Greatest common factor
—
- Least common multiple: —
- Product of the numbers: —
- Are the numbers coprime?: —
On this page
Quick summary: Find the greatest common factor and least common multiple of two whole numbers. Enter the requested values, calculate, review the result, and compare more than one realistic scenario before making a decision.
Read the complete guide
What this calculator estimates
Find the greatest common factor and least common multiple of two whole numbers. It is designed for fast planning and comparison in the United States. The output is an estimate, not a binding quote, approval, tax determination, insurance offer, legal conclusion, medical recommendation or professional advice.
How to use it
Enter the requested values using a single consistent time period and currency. Select Calculate, review the headline result and supporting figures, then change one assumption at a time to compare another scenario.
How the calculation works
The Euclidean algorithm finds the greatest common factor, and the least common multiple is the absolute product divided by that factor.
Important limitations
Inputs must be nonzero whole numbers within ordinary browser integer precision.
Frequently asked questions
Is the result exact?
No. It is a planning estimate based on the assumptions entered.
Can I compare different scenarios?
Yes. Change one input at a time so you can see which assumption changes the result.
Does the calculator store my inputs?
The calculation runs in the browser and does not require an account. Avoid entering unnecessary confidential information.