A free set of health, fitness and nutrition calculators: BMI, body fat, ideal weight, RMR/TDEE, calories, macros, 1RM, running pace and VO2 max. Each one explains the formula step by step and shows the result on a visual gauge — so you understand it, not just read a number. No signup, works right in the browser, in English, Español, Français, Italiano, Deutsch and हिन्दी.