Free calculators and tools for body health, nutrition, fitness, and wellness.
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Discover your biological age based on sleep, exercise, diet, stress, smoking, and alcohol habits. Find out if your lifestyle is ageing you faster or slower than your chronological age.
Try it → ⚖️Calculate your Body Mass Index (BMI) instantly. Find out if you're underweight, normal weight, overweight, or obese, and get your personalized healthy weight range.
Try it → 🔬Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) using the Mifflin-St Jeor equation. Understand how many calories your body burns at rest.
Try it → 📊Calculate your body fat percentage using the US Navy method. Get an accurate body composition estimate based on waist, neck, and hip measurements.
Try it → 🔴Take our burnout risk assessment to find out if you're heading toward burnout. Get a score across 4 dimensions: exhaustion, cynicism, efficacy, and recovery — with a personalized prevention plan.
Try it → 🔥Calculate your daily calorie needs using the Mifflin-St Jeor equation. Find your TDEE, BMR, and personalized calorie targets for weight loss, maintenance, or muscle gain.
Try it → 🎯Find your ideal body weight using four proven clinical formulas (Hamwi, Devine, Robinson, Miller). Get a personalized target weight range based on your height and gender.
Try it → 🥗Calculate your optimal daily macronutrient split — protein, carbohydrates, and fat — based on your body stats and goal. Free, science-backed macro calculator.
Try it → 💪Calculate your ideal daily protein intake based on body weight, activity level, and fitness goal. Get science-backed protein targets for muscle gain, fat loss, or maintenance.
Try it → ❤️Enter your resting heart rate to instantly find out your cardiovascular fitness category — from athlete to at-risk. Includes estimated max HR and heart rate reserve.
Try it → 🪑Calculate the health risk score from your daily sitting time. Discover how much sedentary behavior impacts your longevity and get personalized movement strategies.
Try it → 😴Calculate optimal bedtimes and wake-up times based on 90-minute sleep cycles. Wake up refreshed every morning by timing your sleep to natural REM cycles.
Try it → 👟Convert your daily step count to calories burned. Calculate exactly how many calories you burn walking based on your weight and step count.
Try it → 🧠Take this 5-question Perceived Stress Scale quiz to measure your current stress level. Find out if your stress is low, moderate, high, or very high — and what to do about it.
Try it → 📏Calculate your waist-to-height ratio instantly. Find out if your central body fat level indicates healthy, overweight, or high cardiometabolic risk — more accurate than BMI alone.
Try it → 💧Calculate your ideal daily water intake based on your body weight, activity level, and climate. Get a personalized hydration target in liters and glasses.
Try it → 📅Calculate exactly how many weeks it will take to reach your goal weight based on your daily calorie deficit. Uses the 7,700 kcal per kg scientific formula.
Try it → 📈Calculate exactly how many weeks it will take to reach your goal weight based on your daily calorie surplus. Science-based timeline for muscle gain.
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