Miscellaneous

The miscellaneous calculators are everyday utilities — tip and bill splitting, sales tax, percentages, fractions, unit conversions, GPA, age, date arithmetic, gas mileage, color contrast, password strength, and a scientific calculator. Each one is small in scope and built to do one job well.

These are designed for the dozens of small numerical questions that come up in a normal week and don't justify opening a spreadsheet. The color-contrast checker doubles as a WCAG 2.1 reference for designers and developers building accessible interfaces.