About Fraction Simplifier
Fraction Simplifier reduces a fraction to its lowest terms. Give it a numerator and a denominator and it shows the original pair, the reduced pair and, when the reduction reaches a whole number, that whole number as well. Enter 18 over 24 and the page answers 18/24 = 3/4; enter 10 over 5 and it answers 10/5 = 2/1 = 2.
The reduction divides both terms by their greatest common divisor, and the divisor is taken from the absolute values so the arithmetic behaves the same whichever way the signs point. Both entries are converted to whole numbers before any of that happens, and the conversion floors rather than rounds, so decimal values never reach the divisor step intact.
Two consequences follow. A decimal entry is truncated rather than rounded, and signs are never rearranged: the reduced terms keep the signs they started with, so a negative over a negative stays negative instead of turning positive. There are also only two boxes, with no place for a whole part, so a mixed number has to be rewritten as an improper fraction before it is entered.
How to use Fraction Simplifier
- 1 Enter the numerator in the first box, which starts at 18.
- 2 Enter the denominator in the second box, which starts at 24.
- 3 Press the button to see the fraction reduced to lowest terms.
- 4 Read the last equals sign as the whole number whenever the denominator reduces to one.
Frequently asked questions
What happens if the denominator is zero?
The page returns the message "Denominator cannot be 0" instead of a number. Division by zero is undefined, so the case is reported rather than turned into a meaningless result.
Why was my decimal entry changed?
Both entries are converted to whole numbers first, using a floor rather than a round. 2.9 over 4 therefore becomes 2 over 4 and reduces to one half, and nothing on the page indicates that the discarded fraction was dropped.
Can I enter a mixed number such as one and three quarters?
Not as a mixed number. There are two boxes and no separate whole part, so a value typed with a whole number in front of the fraction is not read that way. Enter it as an improper fraction, seven over four, instead.
Why did my negative fraction stay negative?
The divisor comes from the absolute values of the two terms, which leaves the signs exactly where they were. A negative numerator over a negative denominator therefore reduces to a negative pair rather than being rewritten as a positive fraction.
Free, online, and private
Free to use
Fraction Simplifier is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.
How Fraction Simplifier behaves in detail
These are the specifics of this implementation — the exact ranges, defaults and fixed settings you are working with.
| Parameter | Value |
|---|---|
| Inputs | a numerator and a denominator, defaulting to 18 and 24 |
| Whole-number handling | both terms are floored before anything else happens, so decimal entries are truncated toward zero |
| Zero denominator | reported as "Denominator cannot be 0" instead of producing a number |
| Output shape | the original pair, an equals sign, the reduced pair, then the plain integer when the denominator reduces to 1 |
| Reduction | both terms are divided by the greatest common divisor of their absolute values |
Compiled from the implementation of this tool and checked against it by itoolnet.
What Fraction Simplifier does not do
Knowing the edges of a tool saves more time than another list of its features. These are the cases where it will not do what you might expect.
- Decimal entries are truncated, not rounded. The floor is applied to both terms before any other work is done, so 2.9 over 4 becomes 1/2 - the page reports a simplification of 2/4 and gives no sign that the 0.9 was discarded rather than used.
- Only two-term fractions are supported. A mixed number has to be entered as an improper fraction, seven over four rather than one and three quarters; there is no third term, no nested fraction and no separate whole-number field, so a value typed as "1 3/4" is read as the single number 1.
- Signs are never normalised. The reduction divides by the absolute-value divisor and leaves the signs exactly where they were, so a negative over a negative stays negative over negative - minus six over minus eight comes back as minus three over minus four rather than as three quarters, which is equivalent arithmetic but not the conventional form.
Tested and documented by itoolnet, the team that builds and maintains this site.