Subtracting Fractions Calculator
Subtract fractions easily and see the full step-by-step solution, including LCD and simplifying.
Understanding Fraction Subtraction
Subtracting fractions is similar to adding them; you must have the same denominator before you can subtract the numerators.
Like Denominators
a/c - b/c = (a-b)/cSubtract numerators directly
Unlike Denominators
a/b - c/d = (ad - bc) / bdConvert to common denominator first
Examples
Subtract 3/4 - 1/2
1LCD of 4 and 2 is 4
2Convert: 3/4 - 2/4
3Subtract: (3-2)/4 = 1/4
Frequently Asked Questions
What if the result is negative?
That is perfectly fine in math! It just means the second fraction was larger than the first.
How do I find a common denominator?
The easiest way is to find the Least Common Multiple (LCM) of the two denominators.