About Money Worked Out

Money Worked Out is a set of calculators for UK pay and tax. Each calculator shows its sum line by line, so you can see how the answer was reached and check it yourself.

Who publishes it

The site is published by Sticky Pig Studios. Sticky Pig Studios is not a bank, an adviser or a comparison site, and nobody pays us to show their products.

Other projects from Sticky Pig Studios: Crazy Maths Games and Crazy Science Games.

Why the working is shown

Each calculator on this site lists the steps: which allowance applied, which band each part of your pay fell into and how each deduction was worked out. If one of our steps is wrong, you can see which one and tell us.

Where the figures come from

Every rate, threshold and allowance comes from GOV.UK or another official source. We record where we found each figure and the date we checked it, and we publish that list on the sources page. The methodology page explains how the sums are done, including the rounding.

Before a calculator goes live, we test it against examples with known answers. For most calculators, a second program, written separately from the first, also works out a large set of example calculations. If the two programs disagree, the calculator does not go live.

What the site is not

The calculators show how the rules apply to the figures you enter. They do not tell you what to do with your money. For advice about your own situation, speak to a regulated financial adviser or use the free guidance at MoneyHelper.

Get in touch

You can reach us through the contact page. If you think a figure is wrong, the corrections page explains how to tell us and lists every fix we have made.