Why I Built This
I spent years building software in environments where getting the answer wrong had real consequences — medical robotics, defence, economic forecasting. The standard was high because it had to be.
Then I looked at what NHS workers were using to work out their take-home pay. The tools were full of ads, loaded with tracking scripts, and often got the numbers wrong. Some ran Facebook Pixel and session replay on pages where people entered their salary. Others used flat tax rates with no personal allowance, giving results that were thousands of pounds off.
These are not throwaway tools. People use them to decide whether they can afford to change jobs, reduce their hours, or take on a student loan repayment. If the number is wrong, the decision that follows is wrong too.
I left a good consulting role to build something better. Every calculation on this site cites its source. Every assumption is documented. There are no ads, no tracking scripts, and no black boxes. If the numbers don't match your payslip, you can trace exactly why.
That's the bar. I think these tools deserve it.