Start with what you want to do: add, simplify, convert to a decimal, or find a part of an amount. The table matches one calculator to each task and gives a worked example, so you can spot yours and see what result to expect.
| I want to | Example | Calculator | Result |
|---|---|---|---|
| Add or subtract | 3/4 + 1/2 | Add fractions | 5/4 |
| Convert to a decimal | 3/8 | Fraction to decimal | 0.375 |
| Find a part | 3/4 of 80 | Fraction of a number | 60 |
| Write a part as a fraction | 18 out of 30 | What fraction is it | 3/5 |
| Make a fraction shorter | 18/24 | Simplify fractions | 3/4 |
| Match denominators | LCM of 4 and 6 | Least common multiple | 12 |
| Tell which is larger | 2/3 and 3/5 | Compare fractions | 2/3 is larger |
| Read an improper fraction as a mixed number | 11/4 | Improper to mixed | 2 3/4 |
Each row of the table is an everyday task, with its result in view. If your problem combines more than two fractions in one operation, the main calculator accepts up to twenty. The categories below cover everything else, from the most school-level to the most advanced, and each explains how its tools differ.
A start-to-finish example
Worked example: 1/6 + 1/4 with three calculators
A tank is 1/6 full of water, and you add 1/4 more. What fraction of the tank is full now?
- Recognize the operation. Putting amounts together is addition, so you go to add fractions.
- Find a common denominator. The denominators are 6 and 4, and their LCM is 12.
- Rewrite each fraction. 1/6 = 2/12 and 1/4 = 3/12.
- Add the numerators. 2/12 + 3/12 = 5/12.
- Check whether it can be reduced. The GCF of 5 and 12 is 1, so 5/12 is already in lowest terms.
Result: 5/12 of the tank.
Check: 1/6 ≈ 0.1667 and 1/4 = 0.25 add up to 0.4167, which is 5/12 rounded to four decimal places.
Step 2 is handled by the least common multiple calculator and step 5 by the greatest common divisor one. If you only want the result, the add fractions calculator does all five steps and shows them.
Operations and basics
This is the core of school math: the four operations, simplifying, and comparing. Enter through the operation in your exercise. If you only need to know whether two fractions have the same value, use equivalent fractions or compare instead of calculating. A fraction between two fractions and the missing term are rarer cases worth having at hand.
- Fraction calculator: several fractions and one operation, with the exact result.
- Add fractions: for when the denominators do not match.
- Subtract fractions: the order of the terms changes the sign.
- Multiply fractions: lets you simplify before multiplying.
- Divide fractions: multiply by the reciprocal of the divisor.
- Simplify fractions: divide by the GCF.
- Equivalent fractions: write the same value with larger terms.
- Compare fractions: decide which is larger without converting to decimals.
- Order fractions: sort a list from least to greatest.
- Mixed number calculator: work with numbers like 2 1/3.
- Find a missing numerator or denominator: complete an equation.
- Fraction between two fractions: find one in the middle.
Conversions
One value can be written as a fraction, a decimal, a percent, or a mixed number, and each change has its own calculator. The choice depends on how you have the data, not on what you want to do next. If the decimal has a block that repeats, you need the repeating decimal tool; if it is a percent, use percent to fraction. The page on fraction conversions gathers them all with its own table and the most frequent rounding mistakes.
- Improper fraction to mixed number
- Mixed number to improper fraction
- Fraction to decimal
- Decimal to fraction
- Repeating decimal to fraction
- Fraction to percent
- Percent to fraction
- Approximate a decimal as a fraction: for long measurements, with the error in view.
Here 0.375 is written with a decimal point; the calculators also accept a comma.
Denominators and divisibility
Before adding, subtracting, or comparing fractions with different denominators you need a common multiple, and before simplifying you need a common divisor. The calculators in this section give you those two numbers. The LCM matches denominators and the GCF reduces; the guide on the difference between GCF and LCM explains when each applies. Prime factorization and the list of factors cover the cases where you want to see why two numbers share a factor.
- Least common denominator
- Greatest common divisor (GCF)
- Least common multiple (LCM)
- Prime factorization
- Factors of a number
Applications
These calculators answer questions with units: how much is a part, what is the whole, what fraction one amount is of another. They are easy to mix up, because all three use the same fraction in different ways. If you are not sure which you need, first look at which piece you are missing: the part, the whole, or the fraction. The ones for measurements, recipes, and time turn fractions into everyday units.
- Fraction of a number: the part, from the whole.
- Find the whole from a part and its fraction: the whole, from the part.
- What fraction one amount is of another: the fraction, from the two amounts.
- Average of fractions
- Round to the nearest fraction
- Fractional inches to millimeters
- Scaling recipes with fractions
- Fractions of an hour to minutes
- Proportional sharing
Ratios, proportions, and percentages
A ratio compares two amounts, a proportion sets two ratios equal, and a percent is a ratio with denominator 100. The calculators in this section share a method with fractions and are used when the problem says “for every,” “at a rate of,” or “percent.” The rule of three is the most searched. It works for both direct and inverse proportion, and it helps to know which one you have before calculating.
- Simplify ratios
- Proportion calculator
- Rule of three, direct and inverse
- Ratio to fraction
- Percentage calculator
Advanced arithmetic, algebra, and other representations
These tools are for more advanced courses or for mathematical curiosity. Combined operations, powers, roots, and complex fractions extend the four basic operations. Algebraic fractions, equations, and partial fractions use letters instead of numbers. Continued and Egyptian fractions show other ways to write the same value and are rarely needed in an ordinary exercise.
- Combined operations with fractions
- Powers of fractions
- Roots of fractions
- Complex fractions
- Simplify algebraic fractions
- Equations with fractions
- Partial fraction decomposition
- Continued fractions
- Egyptian fractions
See and practice
If a calculation does not quite make sense, draw it before calculating. The number line puts each fraction in its place and the visual models show parts of a circle or a bar; the visual fractions section gathers both. To train, the worksheet generator creates sheets with solutions and the answer checking tool grades what you type. If you want ready-made sheets to print, they are in fraction worksheets.
If you would rather understand before calculating
A calculator gives the result but does not explain why it comes out that way. For that there are guides and topic sections. What fractions are and the types of fractions help you place the vocabulary, and the glossary defines numerator, GCF, and the rest of the terms. If you always slip at the same point, the guide to common mistakes has checks you can do without a calculator, and the one on why you cannot add denominators clears up the most repeated doubt when adding.
- Operations with fractions
- Fraction conversions
- Divisibility and denominators
- Applications of fractions
- Advanced fractions
- Visual fractions
- Teacher resources
- Solved fraction problems
Sources
English Wikipedia, article Fraction: defines a mixed number as the sum of a non-zero integer and a proper fraction, an improper fraction as one whose numerator is not smaller than its denominator, and notes that adding fractions with different denominators first requires converting them to a common denominator (accessed October 17, 2026).