Notes
How the tools are built and checked, and the occasional piece on the numbers behind them.
How every calculator gets checked before it ships Boundaries, locales and a 375-pixel phone. The three checks every tool passes. Why 2.2 is not enough Rounding a conversion one step too early is the most common bug in this category. Reading an amortisation schedule What the first twelve rows tell you that the monthly payment does not. Ads, and where they are not Why nothing sits above the tool, and what that costs. Dutch and German are longer Designing a layout that survives a 30% expansion.