Fraction Calculator — Add, Subtract, Multiply & Divide
Perform all fraction operations: add, subtract, multiply, and divide. Simplify fractions and find common denominators. Runs locally in your browser.
Features
- ✓Add two fractions with different denominators
- ✓Subtract fractions with automatic common denominator
- ✓Multiply fractions directly
- ✓Divide fractions by inverting and multiplying
- ✓Simplify fractions to lowest terms
- ✓Show decimal equivalent
- ✓Instant calculation as you type
- ✓Perfect for math homework and cooking
- ✓Handles improper fractions
- ✓All calculations run locally in your browser
How to Use
- 1Enter the first fraction (numerator and denominator).
- 2Select the operation (add, subtract, multiply, divide, or simplify).
- 3Enter the second fraction if needed.
- 4View the result as a fraction and decimal.
- 5See the simplified form automatically.
- 6Adjust a recipe by scaling fractions — multiply 3/4 cup by 2 to get 1 1/2 cups, directly in the calculator.
- 7Compare two fractions to see which is larger — subtract one from the other and check if the result is positive or negative.
- 8Simplify a fraction you encounter in carpentry or woodworking — enter 24/32 and instantly get the simplified 3/4.
- 9Convert an improper fraction like 7/4 to its decimal equivalent 1.75 for use in a spreadsheet or financial calculation.
- 10Add up measurements from a tape measure — enter 1/2 + 1/4 + 1/8 to get 7/8 inch for precise woodworking cuts.
Frequently Asked Questions
How do I add fractions with different denominators?
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Find a common denominator (usually the LCM), convert each fraction, then add numerators. For 1/2 + 1/3: common denominator is 6, so 3/6 + 2/6 = 5/6. The calculator does this automatically.
How do I multiply fractions?
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Multiply numerators together and denominators together. For 2/3 × 3/4: (2×3)/(3×4) = 6/12 = 1/2. Always simplify the result.
How do I divide fractions?
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Multiply by the reciprocal (flip the second fraction). For 1/2 ÷ 1/4: 1/2 × 4/1 = 4/2 = 2. The calculator handles this automatically.
What does simplifying a fraction mean?
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Simplifying means reducing to lowest terms by dividing both numerator and denominator by their greatest common divisor (GCD). For 12/16, GCD is 4, so 12÷4 / 16÷4 = 3/4.
Can I use improper fractions?
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Yes. Improper fractions (numerator > denominator) work fine. For example, 7/4 = 1.75. The calculator doesn't convert to mixed numbers, but you can see the decimal equivalent.
Is my calculation data sent to a server?
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No. All calculations happen entirely in your browser using JavaScript. Your fractions and results are never transmitted over the network.
How do I find the least common denominator (LCD)?
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The LCD is the least common multiple (LCM) of the denominators. For 1/3 + 1/5: LCM(3,5) = 15. Convert: 5/15 + 3/15 = 8/15. The calculator finds the LCD automatically for any pair of fractions.
How do I convert an improper fraction to a mixed number?
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Divide numerator by denominator. For 7/4: 7 ÷ 4 = 1 remainder 3, so 1 3/4. The calculator shows the decimal equivalent (1.75) which represents the same value as the mixed number. For exact mixed number display, use a dedicated fraction-to-mixed-number tool.
What does it mean to simplify a fraction?
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Simplifying (reducing) a fraction means dividing both numerator and denominator by their greatest common divisor (GCD). 12/16: GCD(12,16) = 4, so 12÷4 / 16÷4 = 3/4. Simplified fractions are easier to work with and are the standard way to present results.
How do I compare two fractions?
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Cross-multiply: for a/b and c/d, compare a×d vs b×c. If a×d > b×c, then a/b > c/d. For 3/4 vs 2/3: 3×3=9, 4×2=8, 9>8 so 3/4 > 2/3. The calculator can do this by subtracting one fraction from another.
What is a complex fraction?
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A complex fraction has a fraction in the numerator, denominator, or both. For example, (1/2)/(3/4). To simplify: multiply numerator by reciprocal of denominator: 1/2 × 4/3 = 4/6 = 2/3. The calculator handles this by performing the division operation.
Can fractions be used in real-world measurements?
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Yes. Fractions are essential in: cooking (3/4 cup, 1/2 teaspoon), carpentry (3/8 inch, 1/4 inch), sewing (5/8 yard), construction (2/3 of a wall), medicine (1/2 tablet), and finance (1/4 of annual interest). The calculator handles all these real-world scenarios.
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