Fraction Calculator

Add, subtract, multiply, divide fractions and convert to decimal.

Unit & Calculator

Perform arithmetic with fractions effortlessly — add, subtract, multiply, and divide any two fractions and get simplified results instantly. This Fraction Calculator also converts between fractions and decimals, making it a versatile math tool for students, teachers, engineers, and anyone working with fractional numbers. Enter fractions in standard notation (numerator/denominator) and the tool handles finding common denominators, performing the operation, and reducing the result to its simplest form. All calculations run entirely in your browser with no server processing, so your inputs remain private and results appear instantly.

How to use

Result

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Fraction to decimal

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Decimal to fraction

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About Fraction Calculator

The Fraction Calculator is a comprehensive tool for performing arithmetic operations on fractions. It supports addition, subtraction, multiplication, and division of two fractions, automatically finding the least common denominator and simplifying the result using the greatest common divisor (GCD). Beyond arithmetic, it provides bidirectional conversion between fractions and decimal numbers. Enter any fraction as numerator/denominator (e.g., 3/4, 7/8, 15/16) and get accurate results. The tool also handles improper fractions and displays results in their simplest reduced form. All computation happens client-side in your browser — no data is sent to any server, and no account is needed.

How to Use Fraction Calculator

  1. Fraction arithmetic: Enter Fraction A and Fraction B in numerator/denominator format (e.g., 1/2 and 3/4), select the operation (add, subtract, multiply, or divide), and view the simplified result.
  2. Fraction to decimal: Enter any fraction to instantly see its decimal equivalent (e.g., 3/4 = 0.75).
  3. Decimal to fraction: Enter a decimal number (e.g., 0.625) to get its fractional representation (5/8).
  4. Copy the result for use in your calculations, homework, or documentation.

Key Features

  • Four arithmetic operations — Add, subtract, multiply, and divide fractions with automatic simplification.
  • Auto-simplification — Results are always reduced to their simplest form using the GCD algorithm.
  • Decimal conversion — Convert between fractions and decimals in both directions.
  • Improper fraction support — Works with fractions where the numerator is larger than the denominator.
  • Browser-based — All calculations run locally in your browser with zero server dependency.
  • Instant results — No waiting, no loading — see results as you compute.

When to Use This Tool

  • Solving math homework or verifying fraction arithmetic answers.
  • Converting recipe measurements between fractional and decimal formats.
  • Engineering calculations where precise fractional values are needed.
  • Quickly checking if two fractions are equivalent by reducing them to simplest form.
  • Converting between fractional inches and decimal measurements in construction or woodworking.

Technical Details

The calculator parses fractions by splitting on the "/" character to extract numerator and denominator as integers. Arithmetic operations follow standard mathematical rules: addition and subtraction find a common denominator, multiplication multiplies numerators and denominators directly, and division multiplies by the reciprocal of the second fraction. Results are simplified by dividing both numerator and denominator by their greatest common divisor (GCD), computed using the Euclidean algorithm. Decimal-to-fraction conversion uses a continued fraction approximation algorithm to find the closest simple fraction within a reasonable denominator limit. For more number-related tools, check out our Percentage Calculator or Number Base Converter.

Conclusion

The Fraction Calculator makes fraction arithmetic fast and accurate, automatically simplifying results and converting between fractions and decimals. It's a reliable, privacy-friendly math tool that runs entirely in your browser — perfect for students, professionals, and anyone who works with fractions.

Frequently Asked Questions

How do I enter a fraction?
Use the format numerator/denominator, for example 3/4 for three quarters. For mixed numbers like 1½, convert to an improper fraction first (3/2) or use the decimal input (1.5).
Is my data sent to a server?
No. All calculations happen entirely in your browser using JavaScript. Nothing is uploaded or stored on any server.
Why does decimal-to-fraction show an approximation?
Some decimal numbers (like irrational numbers or repeating decimals) cannot be expressed as a simple fraction with a small denominator. The tool finds the closest simple fraction within a reasonable denominator limit.
Can I use negative fractions?
Yes. Enter a negative fraction by placing the minus sign before the numerator (e.g., -3/4). The calculator handles negative values correctly for all four arithmetic operations.