Calculators

Not sure which tool?

Everyday arithmetic that is annoying to get right by hand. The dates group answers how long between two dates, how old something is, when a due date lands, and what a duration is in decimal hours for a timesheet. The money group covers salary, unit price comparisons, fuel, electricity and paint or tiles for a room.

The health and fitness group — body fat, ideal weight, water intake, one-rep max, sleep, pace — are the standard published formulas, and they are estimates by nature. They are useful for tracking a change over time and not a substitute for anyone qualified.

The rest are the ones you reach for mid-task: percentage in all four directions (of, increase, decrease, what percent), aspect ratio for resizing without distortion, square footage and concrete for a job, geo distance between two coordinates, and a plain expression evaluator for when you just want to type the sum.