Free Health & Nutrition Calculators — BMI, BMR, Macro & More
Health and wellness calculators based on established medical formulas. All client-side — your data never leaves your device.
BMI Calculator
Calculate your Body Mass Index instantly. Imperial and Metric units. Color-coded category badge, visual BMI gauge, and healthy weight range for your height. Free, no signup.
Use Tool →BMR Calculator
Calculate your Basal Metabolic Rate and daily calorie needs using the Mifflin-St Jeor equation. Includes TDEE and calorie targets for weight loss, maintenance, and gain. Free, no signup.
Use Tool →Macro Calculator
Calculate your daily protein, carbs, and fat targets for weight loss, maintenance, or muscle gain. Uses Mifflin-St Jeor TDEE with goal-based macro splits. Free, no signup.
Use Tool →Body Fat Calculator
Estimate your body fat percentage using the US Navy method. Male and female formulas. Shows fat mass, lean mass, and body fat category. Imperial and Metric. Free, no signup.
Use Tool →Ideal Weight Calculator
Calculate your ideal weight using four formulas — Hamwi, Devine, Miller, and Robinson — simultaneously. Shows average and BMI healthy range for comparison. Free, no signup.
Use Tool →Water Intake Calculator
Calculate your daily water intake based on weight, activity level, and climate. Shows results in oz, liters, glasses, and standard bottles. Free hydration calculator, no signup.
Use Tool →Calorie Deficit Calculator
Calculate how long it will take to reach your goal weight with a daily calorie deficit. Shows target date, weekly milestones, and warns if deficit is too aggressive. Free, no signup.
Use Tool →BAC Calculator
Estimate blood alcohol content using the Widmark formula. Shows impairment level, time to sober, and legal limit comparison for US, UK, and Australia. For entertainment only.
Use Tool →Caffeine Calculator
Calculate total daily caffeine intake from coffee, tea, and energy drinks. Checks against the 400mg FDA guideline. Shows caffeine half-life chart. Free, no signup.
Use Tool →Smoking Cost Calculator
Calculate how much you spend on cigarettes daily, monthly, and yearly. Shows total spent over years and potential savings if you quit today. Free, no signup.
Use Tool →Pregnancy Weight Gain Calculator
Calculate recommended pregnancy weight gain based on pre-pregnancy BMI using CDC and IOM guidelines. Covers single and twin pregnancies. Free, no signup.
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