About Us

What this site does

You type in a whole number and the calculator lists all of its factors and factor pairs, and shows its prime factorization. There are also tools for the greatest common factor (GCF), the least common multiple (LCM), prime numbers, divisibility and simplifying fractions.

Every result comes with the working, not just the final answer. The idea is that you can follow the steps and then do the next one yourself on paper.

Why it exists

Factors are one of the first topics in school math where many people get stuck. Most online calculators give you a bare list of numbers and leave it there. This site started as an attempt to build the kind of page we wished we had found: a clear explanation, a few worked examples, and a calculator you can check your own work against.

How the content is made

The lessons and worked examples are written and checked by hand, and the calculators are tested against known results. If you ever find a mistake, please tell us. The contact details are on the Contact page and we fix real errors as soon as we can.

The calculators are free to use, need no account, and run in your browser. The pages are built to load quickly and to be easy to read on a phone or tablet.