LCM Calculator

The Least Common Multiple (LCM) is the smallest number that is a common multiple of two or more numbers. For example, the LCM of 4 and 6 is 12. Multiples of 4 are 4, 8, 12, 16... and multiples of 6 are 6, 12, 18... The smallest number appearing in both sequences is 12. Essential for adding and subtracting fractions, LCM is also used in daily life to calculate when periodic events occur simultaneously.

Prime factorization is the most systematic method for finding LCM. Decompose each number into prime factors, then select the highest power of each prime factor and multiply them. For example, 12=2²×3, 18=2×3², so LCM(12,18)=2²×3²=36. This calculator automatically displays the prime factorization of each number, making the calculation process easy to understand.

A factor tree is a diagram that visually shows the process of decomposing a number into prime factors. Divide the number into two factors and continue decomposing each factor until all are prime. For example, 24 decomposes as 24→12×2→6×2×2→3×2×2×2. This calculator draws factor trees with SVG graphics to help you intuitively understand the prime factorization process.

The LCM is the foundation of all common multiples. All common multiples of two numbers are multiples of their LCM. For example, if the LCM of 4 and 6 is 12, the common multiples are 12, 24, 36, 48... i.e., multiples of 12. This calculator automatically lists the first 10 common multiples, clearly showing the relationship between LCM and common multiples. This helps identify repeating patterns of periodic events.

LCM is essential for adding and subtracting fractions. To calculate 1/4 + 1/6, find the LCM of denominators 4 and 6, which is 12, and convert to common denominators: 3/12 + 2/12 = 5/12. Using LCM finds the smallest common denominator, simplifying calculations and making results easier to reduce. When adding multiple fractions, find the LCM of all denominators.