Math · Number Theory

HCF & LCM Calculator

Find the Highest Common Factor (HCF / GCD) and Least Common Multiple (LCM) of up to six numbers — with full prime factorizations.

Euclidean algorithm: gcd(a, b) = gcd(b, a mod b), repeated until the remainder is 0.
Identity: gcd(a, b) × lcm(a, b) = a × b.

Up to 6 numbers

Add or remove inputs freely — HCF and LCM update for the whole set.

Prime factorization

Every input is broken into primes so you can verify the math by hand.

Coprime detection

Know instantly whether a set of numbers shares no common factors.

Euclidean verified

Results cross-check the a×b = HCF×LCM identity automatically.

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