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Add, subtract, multiply, and divide fractions instantly.
Our free fraction calculator performs addition, subtraction, multiplication, and division on fractions and mixed numbers. Results are automatically simplified. The calculator is designed to give a fast answer, but the quality of the answer still depends on accurate inputs and a clear idea of what decision you are trying to support.
- Enter Numerator 1, Denominator 1, and Operation using the same units you plan to compare or report.
- Add Numerator 2 and Denominator 2 and review the inputs before calculating.
- Read the main result first, then use the supporting outputs to understand the trade-offs behind that result.
- Compare your numbers with the worked examples below if you want a quick reasonableness check.
The simplified fraction is the exact mathematical result, while the decimal view helps when you need a more practical or calculator-friendly representation. On this page, the primary output is result.
Scenario 1: 1/2 + 1/3. Inputs used: numerator1: 1, denominator1: 2, operation: add, numerator2: 1, denominator2: 3. Example result: 5/6. 1/2 + 1/3 = 3/6 + 2/6 = 5/6. Scenario 2: 3/4 * 2/5. Inputs used: numerator1: 3, denominator1: 4, operation: multiply, numerator2: 2, denominator2: 5. Example result: 3/10. Multiply numerators and denominators directly: 3 x 2 = 6 and 4 x 5 = 20, then simplify 6/20 to 3/10.
Core formula: apply fraction operation, then simplify with the greatest common divisor. Fractions are combined according to the selected operation, reduced to their simplest form, and shown as both a fraction and a decimal.
- Addition and subtraction build a common denominator automatically.
- Negative signs are normalized so denominators stay positive.
Use this calculator for homework, recipes, measurements, and any workflow where fractions must be simplified correctly. Related paths for follow-up analysis include percentage calculator, vat calculator, and roi calculator.
Most bad outputs come from a few repeated input errors or interpretation mistakes. Use this short checklist before relying on the result.
- Adding or subtracting fractions without first aligning denominators.
- Forgetting to simplify the final answer.
- Missing sign changes when negative denominators appear.
