Hydration & Lifestyle calculators

Water, alcohol, caffeine, sun and habits.

Daily water needs for your weight, exercise and climate.

Weekly alcohol units and calories from your drinks.

Rough BAC estimate and time to sober, using Widmark.

Add up caffeine from coffee, tea, soda and energy drinks.

What smoking costs and what you save by quitting.

Estimated time to burn with and without sunscreen.

Build up your steps gradually toward a goal.

How much of your waking day you spend sitting.

Money, calories and units avoided since you stopped.

How far along you are toward making a habit automatic.

Related guides

Liquid calories add up quickly and do not fill you up.

Quality and context matter more than raw hours.

Why 21 days is a myth and what the research really says.