What is an equivalent fractions calculator?
An equivalent fractions calculator takes a fraction and produces another fraction that represents the exact same value but is written with different numbers. Two fractions are equivalent when they describe the same portion of a whole: 1/2, 2/4, and 3/6 all point to the same amount even though the digits look different. This tool builds an equivalent fraction by scaling the one you enter, and it also shows the simplest form of your original fraction.
How does it work?
To create an equivalent fraction, multiply both the numerator and the denominator by the same non-zero number, called the multiplier. Scaling the top and bottom by the same factor leaves the overall value unchanged, because you are really multiplying the fraction by a disguised form of 1, such as .
Given a numerator , a denominator , and a multiplier , the equivalent fraction is:
The simplest form runs the same idea in reverse. Instead of multiplying, you divide the numerator and denominator by their greatest common divisor (GCD), the largest whole number that divides both exactly:
The GCD is computed with the Euclidean algorithm, which repeatedly replaces the larger number with the remainder of dividing it by the smaller until the remainder reaches zero.
How to use the calculator
- Enter the numerator of your starting fraction.
- Enter the denominator.
- Choose a multiplier (2 or greater) to scale the fraction up.
- Read the equivalent numerator and equivalent denominator, which together form the scaled fraction.
- Read the simplified numerator and simplified denominator to see your original fraction in lowest terms.
Worked examples
Start with 1/2 and a multiplier of 3. Multiplying the top and bottom by 3 gives:
Because 1 and 2 share no common factor other than 1, the simplest form of the original is still 1/2.
Now take 2/4 with a multiplier of 2. Scaling gives the equivalent fraction:
The GCD of 2 and 4 is 2, so the simplest form of the original fraction is:
As a final example, the fraction 3/9 reduces using a GCD of 3:
Practical notes
Equivalent fractions are essential whenever you need a common denominator, for example when adding or comparing fractions with different bottoms. Scaling each fraction so they share the same denominator lets you work with the numerators directly. The simplest form, on the other hand, gives the cleanest way to report a result and makes it easy to recognise when two answers are actually the same.
If you only need to reduce a fraction, the fraction simplifier and simplify fractions tools focus on that step, while the fraction to decimal calculator converts a fraction into its decimal value.
FAQ
Why must the multiplier be 2 or greater? A multiplier of 1 would return the same fraction, and 0 would collapse it to 0/0. Using a whole number of 2 or more guarantees a genuinely different but equivalent fraction.
Does multiplying change the value of the fraction? No. Multiplying the numerator and denominator by the same non-zero number is equivalent to multiplying by 1, so the value is preserved even though the written form changes.
What if my fraction is already in lowest terms? Then the simplified result equals your input. For instance, 1/2 stays 1/2 because the GCD of 1 and 2 is 1.