Category

Health calculators

Free, evidence-based health calculators. BMI, BMR (Mifflin-St Jeor), calorie needs, body fat (US Navy method), ideal weight (Devine/Robinson/Miller/Hamwi), water intake, sleep cycle, one-rep max, lean body mass, macro split, period & ovulation, and pregnancy due date. All formulas cited to peer-reviewed source.

14 calculators in this category.

Frequently asked questions

Which BMR formula is most accurate?

Mifflin-St Jeor (1990) is the modern gold standard for adults — most accurate for the general population. The BMR Calculator uses Mifflin-St Jeor by default. Harris-Benedict is older and tends to overestimate slightly. Both are estimates; individual variation can be ±200 kcal.

Is BMI accurate?

BMI works as a population-level screening tool but has known blind spots: it doesn't distinguish muscle from fat (athletes register as overweight), it varies by ethnicity (Asian populations have higher health risks at lower BMI), and it doesn't account for body fat distribution. Use it alongside body fat % and waist-to-hip ratio for a fuller picture.

How much water do I actually need?

Roughly 33 ml per kg bodyweight as a baseline (about 2.3 L for a 70kg person), plus an extra 500-1000 ml for moderate exercise and another 500-1000 ml in UAE summer climate. The Water Intake Calculator handles all four variables (weight, activity, climate, pregnancy/breastfeeding).

When should I see a doctor instead of using a calculator?

Calculators are for general guidance. Anything involving symptoms, persistent issues, or medical decisions — see a UAE-licensed doctor. The pregnancy due date, period ovulation, and BMR calculators are educational tools and don't replace medical advice.

Are these calculators safe for children?

Most are designed for adults (18+). BMI ranges for children differ by age and sex. The Mifflin-St Jeor BMR formula isn't validated under age 18. For pediatric calculations, use a pediatric BMI calculator at a hospital or your child's doctor.

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