GCF and LCM Calculator
GCF and LCM with stated conventions, validation and a worked example.
Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Exact integer arithmetic uses BigInt. Enter signed decimal integers of at most 200 digits unless a different limit is stated. Decimal approximations are explicitly labelled. LCM is defined as zero when either input is zero.
Example Calculation
- First integer: 18
- Second integer: 24
18 and 24 have GCF 6 and LCM 72.
Frequently asked questions
How do I use this calculator?
Enter first integer, second integer. The result updates automatically. Use Reset to restore the example values.
What method does it use?
Euclidean algorithm gives gcd; lcm=|ab|/gcd for nonzero inputs.. Exact integer arithmetic uses BigInt. Enter signed decimal integers of at most 200 digits unless a different limit is stated. Decimal approximations are explicitly labelled. LCM is defined as zero when either input is zero.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.