Math

GCF Calculator

Find the greatest common factor of two numbers.

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Inputs

Adjust the assumptions to match your scenario. Results update instantly.

Results

Primary outputs and comparison insights are built from the current inputs.

GCF

12

Greatest common factor.

LCM

72

Least common multiple.

Product

864

Product of the two numbers.

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How this calculator works

The GCF Calculator finds the greatest common factor and least common multiple of two integers using the Euclidean algorithm. Enter number 1 and number 2 to estimate gcf, lcm, and product. The calculator updates instantly and adds a comparison table plus chart so you can test the sensitivity of the result before you use it in a decision.

Quick guide

Jump straight to the section you need, then return to the calculator.

Inputs

  • First positive integer.
  • Second positive integer.

Outputs

  • Greatest common factor.
  • Least common multiple.
  • Product of the two numbers.

Assumptions

  • Inputs are positive integers.
  • Uses the Euclidean algorithm for efficiency.

Tips

  • GCF is used for simplifying fractions.
  • LCM is used for finding common denominators.

Formula guide

Use these formulas to audit the output or explain it to someone else.

2 formulas

GCF via Euclidean algorithm
LCM = (a × b) ÷ GCF

Usage examples

Review a ready-made scenario, copy it, then tweak inputs to match your case.

Example

2 inputs3 outputs

Fraction simplification

Inputs

  • Example input Number 1: 48
  • Example input Number 2: 18

Outputs

  • Example result GCF: 6
  • Example result LCM: 144
  • Example result Product: 864

GCF of 48 and 18 is 6, so the fraction 48/18 simplifies to 8/3.

GCF by second number

5 of 5 rows
Number 2GCFLCM
262312
311744
361272
411984
462552

GCF × LCM = Product of the two numbers.

GCF pattern

Highest: 36 (12)Lowest: 31 (1)
Number 2GCF

Focus point

26

2

Position

#1 of 5

Original order

Share of total

11.11%

Total: 18

PositiveNegative

GCF × LCM = Product of the two numbers.

References

  • Euclidean algorithm for GCD
  • Number theory fundamentals

FAQ

Common questions

What does the GCF Calculator do?

The GCF Calculator finds the greatest common factor and least common multiple of two integers using the Euclidean algorithm. Enter number 1 and number 2 to estimate gcf, lcm, and product. The calculator updates instantly and adds a comparison table plus chart so you can test the sensitivity of the result before you use it in a decision. It is part of our math toolkit.

What inputs do I need?

Typical inputs include First positive integer., Second positive integer..

How are the results calculated?

We follow the formulas and assumptions outlined in the "How this calculator works" section. You will see outputs like Greatest common factor., Least common multiple., Product of the two numbers..

Can I share or download the results?

Use the Copy link or Print buttons to share your results. If a table or chart appears, you can download the data as CSV.

Is my data stored?

No. Calculations run in your browser and we do not store your inputs.