Health & Body Calculators
11 free health & body calculators. Every tool is free, private and works on any device.
BMI Calculator
Calculate your body mass index (BMI) from your height and weight, with UK NHS-style categories and a healthy weight range for your height.
BMR Calculator
Work out your basal metabolic rate (BMR) — the calories your body burns at complete rest — using the Mifflin-St Jeor equation.
TDEE Calculator
Calculate your total daily energy expenditure (TDEE) from your BMR and activity level, plus calorie targets for losing, maintaining or gaining weight.
Calorie Deficit Calculator
Find a safe daily calorie deficit for your weight-loss goal, and see the predicted weekly weight loss and time to reach your target weight.
Protein Intake Calculator
Calculate how much protein you need per day based on your weight, activity level and goal — from general health to muscle building.
Macro Calculator
Split your daily calories into protein, carbohydrate and fat targets based on your goal — cutting, maintaining or bulking.
Water Intake Calculator
Estimate how much water you should drink each day, adjusted for your body weight, activity level and climate.
Body Fat Calculator
Estimate your body fat percentage from simple tape measurements using the US Navy method, with healthy range guidance.
Ideal Weight Calculator
Calculate your ideal body weight (IBW) and adjusted body weight using the Devine, Robinson, Miller and Hamwi formulas.
Lean Body Mass Calculator
Calculate your lean body mass (LBM) and fat mass from your height, weight and gender using the Boer formula.
Body Surface Area Calculator
Calculate body surface area (BSA) using the Mosteller, Du Bois and Haycock formulas — a standard input for clinical dosing.