Health Calculators
Free tools for BMI, calorie needs, pregnancy tracking, and more. Results run locally in your browser — nothing is stored or transmitted.
BMI Calculator
Calculate Body Mass Index from height and weight in metric or imperial units.
Calorie Calculator
Estimate daily calorie needs using the Mifflin-St Jeor equation.
TDEE Calculator
Find your Total Daily Energy Expenditure based on activity level.
Baby Due Date Calculator
Calculate estimated due date and week-by-week pregnancy milestones.
Age & Date Calculator
Calculate exact age, days between dates, and future date countdowns.
About these health calculators
These tools cover the most common health and wellness calculations: body composition screening, energy balance, pregnancy planning, and date-based tracking. All formulas are based on established clinical and research standards, including the Mifflin-St Jeor equation for calorie estimation and the Naegele rule for due date calculation.
These calculators are informational tools — they are not substitutes for medical advice. If you have health concerns or are managing a condition, use these outputs as a starting point for conversations with your healthcare provider.
Frequently asked questions
Which calorie calculator should I use — calorie or TDEE?
Start with the TDEE calculator if you want your total daily energy expenditure broken down by activity level. Use the calorie calculator if you want a goal-oriented output (maintain, lose, or gain) with the deficit or surplus already calculated. Both use the same underlying formula — the TDEE calculator shows the components, the calorie calculator shows the targets.
Is BMI a reliable health indicator?
BMI is a population-level screening tool, not a clinical diagnosis. It does not distinguish between muscle and fat mass and performs poorly for athletes, older adults, and certain ethnic groups. Use it alongside other indicators — waist circumference, blood pressure, blood glucose — for a more complete picture. See the BMI calculator for a full discussion of its limitations.
How accurate is the due date calculator?
The baby due date calculator uses the standard Naegele rule: last menstrual period plus 280 days. It is the same method used by most OB/GYN providers for initial estimates. Only about 5% of births occur on the exact estimated due date — most occur within a two-week window. Your provider may adjust the estimate based on first-trimester ultrasound measurements.