This section is the maths toolbox: the calculations that come up in school, at work and in every other section of this site. Each calculator does more than hand back a number. It shows the working, step by step, so the answer can be checked, learned from, or used to mark homework honestly.
Start with the two tools almost everyone needs at some point: percentages in their many forms, and fractions added, compared and simplified with the steps shown.
More calculators for this section are finished and published in stages, and this page grows as they go live.