GCF and LCM Calculator
Calculate the Greatest Common Factor (GCF) and Lowest Common Multiple (LCM) of up to 10 numbers. Shows prime factorisation.
How to use the GCF / LCM Calculator
Enter your numbers
Type 2–10 whole numbers separated by commas or spaces. Both the GCF (Greatest Common Factor, also called HCF) and LCM (Lowest Common Multiple) are calculated instantly. Works with any positive integers.
What GCF and LCM mean
The GCF is the largest number that divides evenly into all your numbers — useful for simplifying fractions. The LCM is the smallest number that all your numbers divide evenly into — useful for finding common denominators. The factorisation table shows how each number breaks down into prime factors.
Frequently asked questions
Is the GCF / LCM Calculator free to use?
Yes, the GCF / LCM Calculator is completely free. There is no sign-up, no account required, and no limit on how often you can use it.
How accurate is the GCF / LCM Calculator?
The GCF / LCM Calculator uses standard mathematical formulas and produces results accurate to standard precision. For critical applications, always verify with an authoritative source.
What devices does the GCF / LCM Calculator work on?
The GCF / LCM Calculator works on any device with a modern web browser — desktop, laptop, tablet, or phone. It is mobile-friendly and works offline once the page has loaded.