MathsLive

Fraction Calculator

Add, subtract, multiply or divide two fractions and see the simplified result.

Short answer

Enter the two fractions and pick an operation. The answer is shown both as a simplified fraction and a decimal.

Fractions

Numerator 1

Denominator 1

Operation

Numerator 2

Denominator 2

Fill in the fields above to see your result instantly.

Calculation method, coverage and version

Inputs used: Numerator 1, Denominator 1, Operation, Numerator 2, Denominator 2.
Calculation approach: The calculator applies the rules and assumptions described in “How it works” to the values you enter. Rounding can cause small differences from an official or provider calculation.
Coverage: Maths. UK nations, tax treatment, local rules and provider criteria can differ; check the official sources shown below before acting.
Content version: No page-specific review date is currently published. Treat the result as indicative and verify current rules independently.

Not included unless explicitly requested: personal circumstances not entered, provider discretion, future rule changes, professional fees and case-specific exceptions. Read the full calculator methodology.

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.

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Percentage Calculator →Ratio Calculator →