Health Calculators
Tools in This Collection
BMI Calculator
Calculate Body Mass Index from weight and height.
Calorie Calculator
Estimate daily calorie needs based on age, weight, height, and activity level.
Macro Calculator
Calculate daily macronutrient targets based on calorie goals.
Water Intake Calculator
Calculate recommended daily water intake.
Body Fat Calculator
Estimate body fat percentage using the US Navy method.
Sleep Cycle Calculator
Calculate optimal wake-up or bedtimes based on sleep cycles.
Age Calculator
Calculate your exact age in years, months, and days from your date of birth.
Frequently Asked Questions
- How accurate are online BMI calculators?
- BMI calculators use the standard formula (weight divided by height squared) and are accurate for that calculation. However, BMI does not account for muscle mass, bone density, or body composition, so it is best used as a general screening tool alongside other measurements.
- How many calories should I eat per day?
- Daily calorie needs depend on your age, sex, weight, height, and activity level. Our calorie calculator uses the Mifflin-St Jeor equation to estimate your basal metabolic rate, then adjusts for your activity level and goals.
- How much water should I drink daily?
- A common guideline is half your body weight in ounces. Our water intake calculator personalizes the recommendation based on your weight, activity level, and climate to give you a more accurate daily target.