Health & Fitness Calculators
Science-based tools to help you understand your body and reach your fitness goals.
Our 16 health calculators use clinically validated formulas from the World Health Organization (WHO), National Institutes of Health (NIH), and the American College of Sports Medicine (ACSM). Calculate your BMI, find your daily energy expenditure, plan macro targets, or estimate your calorie needs for weight loss, maintenance, or muscle gain. All results are instant, private, and free.
BMI Calculator
Calculate your Body Mass Index and understand what your BMI means for your health.
TDEE Calculator
Find your Total Daily Energy Expenditure to plan your diet for weight loss, maintenance, or muscle gain.
Calorie Calculator
Calculate your daily calorie needs based on age, sex, height, weight, activity level, and fitness goals.
Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy method. See your fat mass, lean mass, and fitness category.
Ideal Weight Calculator
Find your ideal body weight using four proven medical formulas. Compare results by height and frame size.
Pregnancy Due Date Calculator
Calculate your estimated due date, current pregnancy week, trimester, and key milestone dates.
Pace Calculator
Calculate running pace, speed, distance, or finish time. Plan your training for 5K, 10K, half marathon, and marathon.
Ovulation Calculator
Predict your most fertile days and ovulation date based on your menstrual cycle. Plan or prevent pregnancy naturally.
Sleep Calculator
Find the best time to sleep or wake up based on 90-minute sleep cycles. Optimize your rest for better energy.
Macro Calculator
Calculate your daily protein, carbs, and fat targets based on calories and diet goals. Customize macro splits.
Water Intake Calculator
Find out how much water you should drink daily based on weight, activity level, and climate.
Pregnancy Weight Gain Calculator
Calculate recommended pregnancy weight gain by week based on pre-pregnancy BMI. Track healthy weight targets per trimester.
Protein Intake Calculator
Calculate your daily protein needs based on body weight, activity level, and fitness goals. Includes meal planning breakdown.
BAC Calculator
Estimate your blood alcohol concentration based on drinks consumed, body weight, gender, and time elapsed.
BMR Calculator
Calculate your Basal Metabolic Rate using the Mifflin-St Jeor equation. See daily calorie needs by activity level.
Calorie Deficit Calculator
Calculate your daily calorie target for weight loss using the Mifflin-St Jeor equation with safe deficit recommendations.
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