Fraction Calculator – Add, Subtract, Multiply, Divide & Convert Fractions Online | OmniCalculator

Free online fraction calculator with 6 powerful tools: add, subtract, multiply, divide fractions, convert decimals to fractions, simplify fractions, and handle mixed numbers. Includes formulas, step-by-step guides, and FAQs.

Fraction Calculator - Calculate with Fractions, Mixed Numbers & Decimals

All-in-one fraction calculator for multiple operations: add, subtract, multiply, divide fractions, simplify fractions, convert between decimals and fractions, work with mixed numbers, and handle big numbers. Perfect for students, professionals, and anyone working with fractions and decimals.

What are Fractions?

Mathematics

A fraction represents a part of a whole, expressed as a ratio of two numbers: a numerator (top number) and a denominator (bottom number). For example, 3/4 means 3 parts out of 4 equal parts. Fractions are fundamental to mathematics, appearing in everyday contexts like cooking (1/2 cup flour), time (1/4 hour = 15 minutes), and money (1/4 dollar = 25 cents).

Fractions can be expressed in multiple forms: proper fractions (numerator smaller than denominator, like 3/4), improper fractions (numerator larger than denominator, like 5/3), and mixed numbers (whole number plus fraction, like 1 2/3). All these forms represent the same mathematical value but appear different.

Fractions and decimals are interchangeable ways of representing the same values. 1/2 = 0.5, 1/4 = 0.25, 3/4 = 0.75. Understanding conversions between these formats is essential for flexible mathematical thinking and problem-solving.

Understanding Fractions

Numerator and Denominator

The numerator (top number) indicates how many parts you have. The denominator (bottom number) indicates how many equal parts the whole is divided into. In 5/8, you have 5 parts out of a whole divided into 8 equal parts.

Equivalent Fractions

Equivalent fractions represent the same value: 1/2 = 2/4 = 3/6 = 4/8. Multiply or divide both numerator and denominator by the same number to create equivalent fractions. This principle underlies fraction simplification and common denominator operations.

Simplest Form (Lowest Terms)

A fraction in simplest form has no common factors between numerator and denominator except 1. Simplify by dividing both by their greatest common divisor (GCD). 6/9 simplifies to 2/3 (both divisible by 3).

Common Denominator

To add or subtract fractions, find a common denominator (ideally the least common multiple of the denominators). For 1/3 + 1/4, the LCD is 12, so convert to 4/12 + 3/12 = 7/12.

Mixed Numbers

Mixed numbers combine whole numbers and fractions: 2 1/3 means 2 + 1/3. Convert to improper fractions (numerator ≥ denominator) for calculations: 2 1/3 = 7/3. Convert back to mixed numbers for final answers.

Types of Fractions

Proper Fractions

Numerator is smaller than denominator: 3/4, 5/8, 1/2. Proper fractions represent values less than 1. They're called "proper" because they follow standard rules and conventions.

Improper Fractions

Numerator is greater than or equal to denominator: 5/3, 7/4, 8/8. Improper fractions represent values ≥ 1. They're often converted to mixed numbers for readability but are useful in calculations.

Mixed Numbers

Combination of whole number and proper fraction: 2 1/3, 5 3/4, 10 1/2. Mixed numbers make large fractions more readable. Convert to improper fractions for mathematical operations.

Unit Fractions

Numerator is 1: 1/2, 1/3, 1/8, 1/100. Unit fractions represent one part of the whole. All other fractions can be expressed as sums of unit fractions (Egyptian fraction representation).

Complex Fractions

Fractions where numerator or denominator (or both) contain fractions: (3/4)/(2/5). Simplify complex fractions by dividing: (3/4) ÷ (2/5) = (3/4) × (5/2) = 15/8.

Fraction Calculation Formulas

Adding Fractions (Same Denominator)
a/b + c/b = (a + c)/b

When denominators are equal, add numerators and keep the denominator

Adding Fractions (Different Denominators)
a/b + c/d = (ad + bc)/(bd) = (ad + bc)/(LCD)

Find LCD, convert fractions, then add numerators

Subtracting Fractions
a/b - c/d = (ad - bc)/(bd)

Similar to addition but subtract numerators after finding LCD

Multiplying Fractions
a/b × c/d = (a × c)/(b × d)

Multiply numerators together and denominators together

Dividing Fractions
a/b ÷ c/d = a/b × d/c = (a × d)/(b × c)

Multiply by the reciprocal of the second fraction

Simplifying Fractions (GCD Method)
a/b = (a ÷ GCD)/(b ÷ GCD)

Divide both numerator and denominator by their GCD

Decimal to Fraction
0.75 = 75/100 = 3/4 (simplified)

Place decimal digits over appropriate power of 10, then simplify

Fraction to Decimal
3/4 = 3 ÷ 4 = 0.75

Divide numerator by denominator

Mixed Number to Improper Fraction
a b/c = (a × c + b)/c

Multiply whole number by denominator, add numerator

Improper Fraction to Mixed Number
a/b = (a ÷ b) (a mod b)/b

Divide numerator by denominator to get whole and remainder

Fraction Calculator

Choose the operation you need and enter your values to calculate with fractions, mixed numbers, and decimals.

🔢 Fraction Operations

✂️ Simplify Fractions

🔄 Decimal/Fraction Converter

🔢 Mixed Numbers Calculator

How These Calculators Work

Basic Operations Calculator

Enter two fractions and select the operation. The calculator finds the least common denominator, performs the operation, and returns the result in fraction, decimal, and mixed number formats.

Simplify Fractions Calculator

Enter a fraction to simplify. The calculator finds the greatest common divisor (GCD) of numerator and denominator, then divides both by the GCD to produce the simplest form.

Decimal/Fraction Converter

Convert decimals to fractions by placing the decimal digits over the appropriate power of 10, then simplifying. Convert fractions to decimals by dividing numerator by denominator.

Mixed Numbers Calculator

Convert mixed numbers to improper fractions using the formula: (whole × denominator + numerator) / denominator. Convert improper fractions to mixed numbers by dividing numerator by denominator.

Big Number Handling

These calculators handle large numerators and denominators accurately, maintaining precision even with numbers in the millions. Large fractions are automatically simplified to manageable forms.

Uses of Fraction Calculators

Student Learning and Homework

Students use fraction calculators to check homework, verify calculations, and learn fraction concepts. Seeing multiple representation forms (fraction, decimal, mixed number) reinforces understanding.

Cooking and Baking

Recipes often use fractional measurements (1/2 cup, 3/4 teaspoon). Doubling or halving recipes requires fraction multiplication and division. Calculators quickly convert between measurement units.

Construction and Carpentry

Measurements in inches and feet frequently involve fractions (5 3/8 inches). Calculations for cutting materials, calculating areas, and material quantities rely on fraction mathematics.

Financial Planning

Interest rates, stock prices, and probability calculations use fractions and decimals. Converting between formats helps with financial analysis and investment decisions.

Medicine and Healthcare

Dosage calculations often involve fractions: 1/2 tablet, 3/4 teaspoon. Accurate fraction arithmetic is critical for patient safety in pharmaceutical contexts.

Engineering and Science

Complex calculations in physics, chemistry, and engineering frequently involve fractions. Unit conversions and dimensional analysis require fraction operations.

Music and Art

Musical timing (1/4 note, 3/8 time signature) and proportional measurements in visual arts depend on fractions. Understanding these relationships enhances creative work.

Frequently Asked Questions

What's the difference between a proper fraction and an improper fraction?

A proper fraction has numerator smaller than denominator (3/4, 1/2), representing a value less than 1. An improper fraction has numerator greater than or equal to denominator (5/3, 8/8), representing a value ≥ 1. Both are mathematically valid; improper fractions are often converted to mixed numbers for readability.

How do I add fractions with different denominators?

Find the least common denominator (LCD) of the two denominators. Convert each fraction to an equivalent fraction with the LCD as denominator. Add the numerators and keep the LCD as the denominator. Example: 1/3 + 1/4 = 4/12 + 3/12 = 7/12.

Why do we need to simplify fractions?

Simplifying fractions reduces them to simplest form, making them easier to understand and work with. 6/9 and 2/3 are equivalent, but 2/3 is simpler. Simplified fractions are the standard for final answers in mathematics.

How do I multiply and divide fractions?

Multiply fractions by multiplying numerators together and denominators together: (3/4) × (2/5) = 6/20 = 3/10. Divide fractions by multiplying by the reciprocal: (3/4) ÷ (2/5) = (3/4) × (5/2) = 15/8.

What's the greatest common divisor (GCD)?

The GCD is the largest number that divides both the numerator and denominator evenly. For 12/18, the GCD is 6 (both divisible by 6). Dividing both by 6 gives 2/3. Finding the GCD is essential for simplifying fractions.

Can all decimals be converted to fractions?

Yes, all terminating and repeating decimals can be converted to fractions. Terminating decimals (0.75 = 3/4) convert easily. Repeating decimals (0.333... = 1/3) also convert but may require algebraic manipulation for repeating patterns.

How do I convert a mixed number to an improper fraction?

Multiply the whole number by the denominator, add the numerator, and place the result over the original denominator. For 2 1/3: (2 × 3 + 1)/3 = 7/3. This conversion is necessary for fraction arithmetic operations.

Master Fractions with Confidence

Fractions are foundational to mathematics and appear in countless real-world applications. Whether you're a student mastering fraction arithmetic, a professional needing quick calculations, or someone working on recipes and measurements, these fraction calculators provide accurate, instant results for all your fraction needs.

These calculators not only provide answers but help you understand fraction relationships by showing results in multiple formats (fractions, decimals, mixed numbers). This multi-format approach deepens mathematical understanding and builds confidence in working with fractions.

Note: These calculators handle fractions and mixed numbers of any size. For educational purposes, work through problems manually first to understand the concepts, then use calculators to verify your work and explore variations quickly.