Common Factor Calculator — Every Shared Factor
See the complete list of factors two or more numbers share — not just the greatest one — with each number's own factor list laid out for comparison.
Factors(a) ∩ Factors(b)
COMMON FACTORS
max(common)
GCF
common = {1}
COPRIME
Common Factor Calculator
Every shared factor, not just the greatest
Numbers to Compare
Common Factors
1234612
12
Greatest (GCF)
No
Coprime?
📋 Every Number's Factors
Factors of 24
1234681224
Factors of 36
123469121836
Factors of 60
123456101215203060
Highlighted numbers are shared across every value entered.
How Common Factors Work
🔍 Every Number Has Factors
A factor of a number divides it with no remainder — 24's factors are 1, 2, 3, 4, 6, 8, 12, and 24. We find each number's full list by checking every whole number up to its square root.
🤝 Intersecting the Lists
Once every number's factor list is built, a common factor is simply one that shows up on every single list — the intersection of all of them.
👑 The Greatest One
Of all the common factors, the largest is the GCF — the one most calculators only give you. It's useful for simplifying fractions, but the full list often matters just as much.
1️⃣ The Coprime Case
When the only common factor is 1, the numbers are coprime — a property that matters in cryptography, gear ratios, and scheduling problems where you want cycles that don't sync up too often.
— FAQ