Fraction Simplifier

A fraction simplifier reduces a fraction to its lowest terms. It finds the greatest common factor of the numerator and denominator and divides both by it, so the value stays the same but the numbers get as small as possible. You also get the mixed-number form and the decimal value.

How to use the fraction simplifier

Enter the numerator (top number).
Enter the denominator (bottom number).
Press Calculate to see the simplified fraction and the GCF used.

Formula

\frac{a}{b} = \frac{a \div g}{b \div g}, \quad g = \gcd(a, b)

Worked example: 18/24

Numerator (top): 18
Denominator (bottom): 24

✓ Answer checked

\frac{3}{4}

Decimal: $0.75$

Step-by-step working (2 steps)

Find the greatest common factor Greatest common factor
The largest number that divides both 18 and 24 is 6.
$\gcd(18, 24) = 6$
Divide top and bottom
Divide both numbers by 6.
$\frac{18 \div 6}{24 \div 6} = \frac{3}{4}$

Formulas used

\frac{a}{b} = \frac{a \div g}{b \div g}, \quad g = \gcd(a, b)

How this was checked

✓ Cross-multiplying shows the simplified fraction equals the original.
✓ The new top and bottom share no common factor except 1.

Frequently asked questions

How do I simplify a fraction?

Find the greatest common factor of the top and bottom numbers, then divide both by it. 18/24 has GCF 6, so it simplifies to 3/4.

How do I know a fraction is fully simplified?

A fraction is in simplest form when the top and bottom share no factor other than 1.

Can improper fractions be simplified?

Yes, in the same way. For example, 45/10 simplifies to 9/2, which is 4½ as a mixed number.

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