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Kostenloser Bruchrechner

Addieren, subtrahieren, multiplizieren und dividieren Sie Brüche und gemischte Zahlen – mit vollständigem Rechenweg. Exakte ganzzahlige Arithmetik, gekürzte Ergebnisse, Dezimal- und Prozentwert. Kostenlos und vollständig im Browser.

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Enter two fractions

First fraction

Whole number, then numerator over denominator.

Second fraction

Whole number, then numerator over denominator.

1/2 + 1/3 =

5/6

Mixed number
5/6
Decimal
0.8333333333…
Percentage
83.33%

Step by step

  1. 1Set up: 1/2 + 1/3
  2. 2Common denominator: LCD of 2 and 3 is 6 → 3/6 + 2/6
  3. 3Add numerators: 5/6
  4. 4Simplify: 5/6

Häufig gestellte Fragen

How do I add fractions with different denominators?

Find the lowest common denominator (LCD) of the two denominators, rewrite both fractions over it, then add the numerators and keep the denominator. For 1/2 + 1/3 the LCD is 6, giving 3/6 + 2/6 = 5/6. The calculator shows each of those steps, so you can check your own working rather than just copying an answer.

How do I divide fractions?

Flip the second fraction and multiply. 1/2 ÷ 3/4 becomes 1/2 × 4/3 = 4/6, which simplifies to 2/3. Dividing by zero is undefined, so a second fraction with a numerator of 0 has no answer.

Can it handle mixed numbers like 2 1/2?

Yes. Type the whole number in the first box and the fraction in the two stacked boxes. Mixed numbers are converted to improper fractions internally (2 1/2 becomes 5/2) and the answer is given back in both forms. A minus sign on the whole number applies to the entire value, so -2 1/2 is -5/2, not -3/2.

Why does it say 0.3333333333… instead of 0.3333333333?

Because 1/3 does not terminate as a decimal. The trailing character marks the difference between an exact decimal (3/4 = 0.75) and a rounded one. This is also why the arithmetic itself is done on integers rather than decimals: 1/3 + 1/3 + 1/3 is exactly 1 here, which is not something floating-point decimals can guarantee.

Does it simplify the answer automatically?

Yes. Every result is reduced to lowest terms by dividing the numerator and denominator by their greatest common divisor, and the step-by-step panel names the number it divided by. If the denominator reduces to 1, the answer is shown as a whole number.

Is my data sent anywhere?

No. The calculation runs entirely in your browser — there is no server request, no account and no logging. You can disconnect from the internet and it will still work.

Über Kostenloser Bruchrechner

Kostenloser Bruchrechner ist ein kostenloses, browserbasiertes Tool aus unserer Rechner-Sammlung. Alles läuft lokal auf deinem Gerät — keine Uploads, keine Anmeldung, und deine Daten bleiben privat.