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Calculation details
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What does this calculator estimate?
Simplify fractions calculator: reduce any fraction to lowest terms and convert between improper fractions and mixed numbers with steps shown. Free, no signup.
How this calculator works
Formula
Divide numerator and denominator by their greatest common divisor; decimal = numerator / denominator.
Worked example
42/50 divides by GCD 2 to 21/25, which is 0.84 as a decimal.
Frequently asked questions
How do I use the simplify fractions calculator?
Enter the numerator and denominator of your fraction into the input fields and click the 'Simplify' button to get the result instantly.
Do I need to create an account to use the simplify fractions calculator?
No, the simplify fractions calculator runs entirely in your browser and requires no signup or installation.
Can the simplify fractions calculator handle improper fractions?
Yes, the simplify fractions calculator will reduce any improper fraction to its simplest form or convert it to a mixed number.
Cite this tool
BoringToolsKit. “Simplify Fractions Calculator.” boringtoolskit.com/fraction-simplify-calculator/. Free to reference in articles, syllabi, and answer posts with a link.
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Worked example: reducing 48 over minus 18
Enter 48 in the numerator and -18 in the denominator. The calculator finds the greatest common divisor with the Euclidean algorithm on absolute values: 48 mod 18 = 12, 18 mod 12 = 6, 12 mod 6 = 0, so the loop stops at 6. 12 is not a common divisor because 18 / 12 = 1.5.
Dividing through gives 48 / 6 = 8 and -18 / 6 = -3. Because exactly one of 8 and -3 is negative, the sign prefix is a minus, so the simplified fraction reads -8/3. The decimal line shows 48 / -18 as -2.666667, rounded at the sixth digit from the repeating -2.6666666... . Since 8 exceeds 3, a mixed number line appears too: floor(8/3) = 2 with remainder 2, so the output ends with -2 2/3.
Where the decimal line stops being exact
The decimal line caps at 6 digits after the point and never pads: 1/3 prints 0.333333, 2/3 rounds up to 0.666667, 1/6 prints 0.166667, and 9/3 prints plain 3 with no trailing zeros. The cap rounds rather than truncates, so 1000000/7 prints 142857.142857 while the exact decimal keeps going as 142857.1428571428... . Keep the fraction line for exact values.
Boundary cases change the output shape. With numerator 0 the calculator prints only Result: 0 and skips the divisor, simplified, decimal, and mixed lines, whether the denominator is 5 or -5. With denominator 0 everything is replaced by the division-by-zero error. 4.5 is rejected as not whole, so 4.5/6 needs hand scaling to 9/12 to reach 3/4. Equal inputs collapse: 5/5 reports 1/1 with decimal 1 and no mixed line, since that line needs a numerator strictly greater than the denominator. Negative denominators move their sign to the numerator: 6 over -9 reports -2/3 and decimal -0.666667.