What does it mean to simplify a fraction?

Simplifying (or reducing) means dividing the numerator and denominator by the same number until no whole number bigger than 1 divides both. 12/18 becomes 2/3 — same value, smallest possible numbers.

How do I know a fraction is fully simplified?

When the numerator and denominator share no common factor other than 1 — when their GCF is 1. The calculator checks this and tells you when a fraction is already in simplest form.

Can I simplify a fraction with a negative number?

Yes. Simplify the absolute values as usual and keep a single minus sign in front: −12/18 = −2/3.

What about improper fractions?

They simplify the same way. If the result is still top-heavy, the calculator also shows the mixed-number form — 10/4 simplifies to 5/2, which is 2 1/2.

Fractions & Ratios

Simplify Calculator

Enter a fraction and watch it shrink to simplest form — the GCF found, the division shown, and the mixed-number equivalent included when it applies.

Your numbers

Numerator (top)

Denominator (bottom)

Worked solution

Simplest form

2/3

÷6 cancelled from top and bottom

Both 12 and 18 divide by 6, leaving 2/3 — the same value in the fewest possible pieces.

The working

2 steps

Find the greatest common factor
The GCF is the biggest whole number that divides both the numerator and the denominator.
GCF(12, 18) = 6
Divide top and bottom by the GCF
Dividing both parts by the same number keeps the fraction's value identical — only the pieces change size.
1218
÷ 6 on top and bottom
=
23
nothing bigger than 1 divides both now
12 ÷ 6 = 2 18 ÷ 6 = 3

Works instantly in your browser — nothing is uploaded, and the URL keeps your numbers so you can share the exact worked example.

One step or several?

You can cancel in stages — 12/18 ÷2 → 6/9 ÷3 → 2/3 — or in one move using the GCF: ÷6 straight to 2/3. Both are correct; the GCF route gets you to the finish line in a single division, which is why this calculator leads with it.