Health Calculator
A collection of calculators for health management, such as BMI and water intake.
BMI Calculator
Enter your weight and height to get your BMI and an underweight/normal/overweight/obese cl...
Read MoreDaily Water Intake Calculator
Enter your weight to calculate your recommended daily water intake in milliliters.
Read MoreAbout This Category
Two screening tools: body mass index and a daily water-intake estimate. Both are population-level approximations, useful as a starting point and poor as a verdict about an individual.
BMI ignores muscle mass and fat distribution, so it overstates risk for athletes and understates it for people with normal weight but high visceral fat. Fluid needs vary with body size, activity, climate and diet.
Frequently Asked Questions
Is BMI valid for everyone?
No. It is not designed for children, pregnant people, athletes or adults over 65, and the thresholds that define overweight are population-specific.
How much water should I drink a day?
Roughly 30–35 ml per kilogram of body weight for a sedentary adult in a temperate climate, with food contributing about a fifth. Exercise and heat raise it.
Does coffee count towards fluid intake?
Yes. Moderate caffeine does not offset the fluid it is dissolved in, so tea and coffee count, though water remains the better default.
Calculators in This Category
Sources & last update
2026-10-19