Fractions: adding and subtracting
Calculator shows how to add or subtract two fractions step by step. Simply enter two fractions, select add or subtract and get list of all partial steps needed to compute result. Train your math with calculla!

How to use this tool

Calculator shows how to add (subtract) two fractions. Enter input fractions and select needed operation (addition or subtraction) in form below and calculla will compute the results by performing following steps:
  • I. Convert input fractions into improper form. If your fractions do not containt wholes part, then this step is unnecessary and can be skipped.
  • II. Find common denominator. If input fractions already have common denominator, this step can be skipped.
  • III. Perform operation. In this step, calculla adds (subtract) nominators and saves denominator without changes.
  • IV. Get wholes part out of result. This step is needed only if result is improper fraction i.e. its nominator is greater than denominator.
  • V. Shortening result to the simplest form.

Links to external sites (leaving Calculla?)

Ancient version of this site - links

"Calculla v1" version of this calculatorIn December 2016 the Calculla website has been republished using new technologies and all calculators have been rewritten. Old version of the Calculla is still available through this link: v1.calculla.com. We left the version 1 of Calculla untouched for archvial purposes.
Direct link to the old version:

Diagram showing how to add (subtract) two fractions

IIIIIIIVV
=
11
4
=
5
4
=
5 ·3
4 ·3
=
15
12
=
31
12
=
27
12
=
27
12
=
11
3
=
4
3
=
4 ·4
3 ·4
=
16
12

Summary - add (subract) step by step

StepsIIIIIIIVV
Summary
11
4
+
11
3
=
5
4
+
4
3
=
5 ·3
4 ·3
=
15
12
+
16
12
=
31
12
=
27
12
=
27
12
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