How is GCD calculated internally?

The calculator uses the Euclidean algorithm, repeatedly replacing the larger number with the remainder of dividing it by the smaller number.

GCD & LCM Calculator

Calculate the GCD (greatest common divisor) and LCM (least common multiple) of two positive integers using the Euclidean algorithm relationship.

Inputs

Results

Try an example

Formula

LCM(a,b) = (a × b) / GCD(a,b)

GCD, LCM, Permutations, and Combinations Explained

The Euclidean algorithm behind GCD/LCM, and the factorial math behind permutations and combinations.

Percentage Calculator

Find what percentage one number is of another, or calculate percentage change.

Percentage Change Calculator

Calculate the percentage increase or decrease between two values.

Quadratic Equation Solver

Solve ax² + bx + c = 0 for real roots using the quadratic formula.

Average (Mean) Calculator

Calculate the average of up to 10 numbers.

Standard Deviation Calculator

Calculate the population standard deviation of up to 5 numbers.

Circle Area & Circumference Calculator

Calculate the area, circumference, and diameter of a circle from its radius.