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Fraction Calculator
Fractions
Fill in the fields above to see your result instantly.
How it works
Standard fraction arithmetic: cross-multiply for + and −, multiply numerators and denominators for ×, multiply by the reciprocal for ÷. The result is then divided by the greatest common divisor (GCD) to simplify.
Worked example
1/2 + 1/3 = (1×3 + 1×2) / (2×3) = 5/6 ≈ 0.8333
Who should use this
- •Students learning fractions
- •Anyone scaling up a recipe
- •DIY measurements
Common mistakes
- ×Forgetting to find a common denominator before adding
- ×Multiplying instead of cross-multiplying
Frequently asked questions
What is GCD?▾
Greatest Common Divisor — the largest whole number that divides both the numerator and denominator.
Can I enter negative fractions?▾
Yes — put the minus sign on the numerator.