Add, subtract, multiply, and divide fractions instantly with step-by-step solutions. Simplify fractions to their lowest form and convert between fractions and decimals. Free online fraction calculator for homework, cooking, and everyday math.
A fraction is simply a way to show a part of something. Think of a pizza cut into 8 equal slices. If you grab 3 of those slices, you are holding 3/8 of the pizza. The top number (3) is called the numerator — it counts how many parts you have. The bottom number (8) is the denominator — it tells you how many equal parts make up the whole thing.
One important rule: the denominator can never be zero. Dividing by zero just does not work in math, so a fraction like 5/0 has no meaning. Beyond that, fractions can be small, large, proper, improper, or mixed — and our calculator handles all of them.
Before diving into calculations, it helps to know the three basic types you will run into.
The numerator is smaller than the denominator. Like 2/5 or 3/8. The value is always less than 1.
The numerator is bigger than the denominator. Like 7/4 or 11/3. The value is greater than 1.
A whole number plus a fraction. Like 2 1/3. Useful for everyday measurements like recipes.
Using the calculator is straightforward. Here is what you do:
Quick example: Adding 1/2 and 1/3. The calculator finds a common denominator of 6, converts to 3/6 and 2/6, adds them to get 5/6, and simplifies the result. All shown step by step.
Adding fractions is not like adding whole numbers. You cannot just add across the top and bottom. First, both fractions need the same denominator.
The easiest method is to multiply each fraction by the other denominator. For 1/4 plus 1/6, multiply the first by 6/6 and the second by 4/4. You get 6/24 plus 4/24, which equals 10/24. Simplify that to 5/12.
Subtraction works the same way. Find a common denominator, subtract the numerators, and keep the denominator. The formula flips just one sign: (a×d - b×c) / (b×d).
Multiplication is actually the easiest operation with fractions. No common denominator needed. Just multiply straight across.
For 2/3 times 3/5, multiply the numerators (2×3=6) and the denominators (3×5=15). You get 6/15, which simplifies to 2/5.
A handy tip: if you are multiplying a fraction by a whole number, just write the whole number over 1. So 4 becomes 4/1, then multiply as usual. 2/3 × 4 = 2/3 × 4/1 = 8/3 = 2 2/3.
Division sounds tricky but there is a simple trick: flip the second fraction and multiply instead. This is called multiplying by the reciprocal.
For 3/4 divided by 2/5, flip 2/5 to get 5/2. Then multiply: 3/4 × 5/2 = 15/8 = 1 7/8. That is all there is to it.
Many people remember this as Keep-Change-Flip. Keep the first fraction, change the division sign to multiplication, and flip the second fraction. Three simple steps that work every time.
A fraction is simplified when the numerator and denominator share no common factors besides 1. To simplify, find the greatest common divisor (GCD) of both numbers and divide each by it.
Take 18/24. The GCD of 18 and 24 is 6. Divide both by 6 and you get 3/4. That is the simplified form.
Our calculator automatically simplifies every answer. You will always see the result in its cleanest form, whether it is a proper fraction, an improper fraction, or a mixed number.
Every fraction is really just a division problem waiting to be solved. The line between the numerator and denominator means divided by. So 3/4 is simply 3 ÷ 4, which equals 0.75.
Going the other way, to turn a decimal into a fraction, figure out what place the last digit occupies. For 0.625, the 5 is in the thousandths place, so write it as 625/1000. Then simplify by dividing both by 125 to get 5/8.
Some fractions produce repeating decimals, like 1/3 = 0.333... The calculator can show these as rounded decimals or keep them in exact fraction form so you never lose precision.
Fractions trip up even confident math students. Here are the biggest pitfalls to watch out for.
Adding denominators together
When adding 1/2 + 1/3, some people write 2/5 by adding both tops and both bottoms. That is wrong. You must find a common denominator first. The real answer is 5/6.
Forgetting to simplify
Getting 4/8 as an answer is technically correct, but it is not finished. Always check if both numbers can be divided by the same value. 4/8 simplifies to 1/2.
Mixing up the division rule
When dividing fractions, people often flip the wrong one. Remember: flip the second fraction, not the first. Keep-Change-Flip saves the day here.
Ignoring mixed numbers
If your answer is 7/4, write it as 1 3/4. Improper fractions are fine in algebra, but mixed numbers are usually preferred for everyday answers.
Fractions are not just for textbooks. They show up constantly in everyday situations.
Always look for a common denominator before adding or subtracting. It is the single most important step.
Simplify early if you can. Working with smaller numbers reduces mistakes.
Check your answer by converting to decimals. If 3/4 plus 1/2 equals 1.25 as a decimal and 5/4 as a fraction, both should match.
When in doubt, write it out. Drawing a pie or a bar can make abstract fractions feel real.
Find a common denominator by multiplying each fraction by the other denominator. For 1/4 plus 1/6, multiply the first by 6 and the second by 4 to get 6/24 and 4/24. Add to get 10/24, then simplify to 5/12. Our calculator does all of this automatically and shows every step.
Use Keep-Change-Flip. Keep the first fraction exactly as it is. Change the division sign to multiplication. Flip the second fraction by swapping its numerator and denominator. Then multiply straight across. So 3/4 divided by 2/5 becomes 3/4 times 5/2, which equals 15/8 or 1 7/8.
Simplifying makes fractions easier to understand and compare. The fractions 4/8 and 1/2 represent the exact same amount, but 1/2 is much clearer. In tests and real life, simplified answers are usually expected. Our calculator simplifies every result automatically.
Multiply the whole number by the denominator, then add the numerator. Place that over the original denominator. For 2 3/4, multiply 2 by 4 to get 8, add 3 to get 11, so the improper fraction is 11/4. This is useful when you need to multiply or divide mixed numbers.
Absolutely. A negative fraction simply means a negative value. The negative sign can go in front of the fraction, in the numerator, or in the denominator. All three represent the same value. For example, -1/2 is the same as -1 over 2 or 1 over -2.
A fraction is undefined when its denominator equals zero. Division by zero has no meaning in mathematics. So 5/0, or any fraction with zero on the bottom, does not represent a real number. Our calculator will alert you if you accidentally enter a zero denominator.