Health calculators
Free online BMI, calorie, pregnancy, and health calculators — quick answers about your body.
Back-of-the-envelope numbers for everyday health questions. Not medical advice — just math.
- BMI Calculator
Calculate your body mass index from height and weight in imperial or metric units, with CDC weight classification and healthy weight range for your height.
- BMR Calculator
Calculate your Basal Metabolic Rate using three formulas — Mifflin-St Jeor, Harris-Benedict (revised), and Katch-McArdle (requires body fat %) — in imperial or metric units.
- Calorie Calculator
Estimate daily calorie needs using the Mifflin-St Jeor BMR formula with your activity level and weight goal. Includes macro breakdown for protein, carbs, and fat.
- Pregnancy Due Date Calculator
Estimate your due date using Naegele's rule from the first day of your last period or conception date. Shows gestational week, trimester, days remaining, and progress.
- TDEE Calculator
Calculate Total Daily Energy Expenditure from your BMR and activity level. Set a weight goal to get your calorie target and macro breakdown.