Health Calculators
The health calculators here turn everyday questions — is my weight in a healthy range, how many calories do I need, when is my baby due — into numbers built on a named formula: the WHO's BMI classification, the Mifflin-St Jeor equation, Naegele's rule.
They estimate where you fall against population reference ranges, not your personal health outcome, so treat any result that concerns you as a reason to ask a doctor, dietitian, or midwife — not as a diagnosis.
- BMI CalculatorEnter your weight and height to calculate your Body Mass Index (BMI), a quick screening measure used worldwide to estimate whether your weight falls in a healthy range for your height.Shows its formula3 figures checked · 2026-08-13
- Body Fat Percentage CalculatorWith your height, neck, waist, and (if female) hip measurements, this calculator estimates your body fat percentage using the U.S. Navy circumference method — no calipers or scans required, just a tape measure.Shows its formula1 figures checked · 2026-08-14
- TDEE CalculatorEnter your sex, age, weight, height, and activity level to estimate your Total Daily Energy Expenditure (TDEE) — the number of calories your body burns in a typical day, including movement and exercise.Shows its formula
- Due Date CalculatorEstimates your due date, trimester and full-term dates from your last period and cycle length. Not a substitute for medical care.Shows its formula2 figures checked · 2026-08-22
- Ovulation & Fertile Window CalculatorFrom the start date of your last period and your typical cycle length, this calculator estimates your ovulation date, your fertile window, and your next expected period.Shows its formula2 figures checked · 2026-08-22