Calculator
Age Calculator
Exact age in years, months, and days from date of birth — plus next birthday and life-stage context for health screening.
Calendar-accurate date difference
Free Health Tools & Medical Calculators
BMI, pregnancy, calories, medication reminders & more — free educational tools. Not a substitute for clinical care.
Calculator
BMI Calculator
Calculate Body Mass Index using WHO international weight categories. Instant underweight, normal, overweight, or obesity classification.
WHO: weight (kg) divided by height (m) squared
Calculator
Calorie Calculator
Free calorie calculator: estimate daily calories (BMR & TDEE) for weight maintenance, loss, or gain using age, sex, height, weight, and activity.
Mifflin-St Jeor BMR with activity multiplier
Calculator
BMR & TDEE Calculator
Basal metabolic rate and total daily energy expenditure using the Mifflin-St Jeor equation.
Mifflin-St Jeor BMR x activity factor
Calculator
Pregnancy Calculator
Due date, gestational age, and trimester from LMP or conception date with week-by-week timeline.
Naegele rule (LMP + 280 days)
Calculator
Ideal Weight Calculator
Healthy weight range from height and sex using the Robinson formula with plus/minus 10% band.
Robinson formula by height and sex
Calculator
Water Intake Calculator
Daily fluid intake in litres and cups from body weight and activity level.
33 ml per kg with activity adjustment
Daily care
Medication Reminder
Free medication reminder: personal dose schedule stored in your browser. Confirm all prescriptions with your pharmacist.
Browser-local schedule
Reference
Lab Result Guide
Compare a lab value to common reference intervals. Always follow the range on your own report.
Common lab reference intervals
Reference
Child Growth Percentiles
WHO weight-for-age percentile estimate for children 24–60 months.
Simplified WHO growth curves
Reference
Common Symptoms
Browse symptoms by body area with plain-language explanations and when to seek urgent care.
Curated symptom library with body map
Reference
Common Diseases & Conditions
Search conditions with overview, typical symptoms, and links to find specialists.
Indexed condition articles
Reference
Medical Glossary
Look up medical terms, abbreviations, and definitions from reports and prescriptions.
Searchable A-Z terminology
Wellness
Weather & Air Quality
Temperature, humidity, UV index, and air quality for any city — asthma, allergies, and travel planning.
Open-Meteo weather and AQI
Travel
Currency Converter
Convert medical travel costs between currencies for international care planning.
Live exchange rate lookup
Travel
Flight Search
Search flights for medical tourism and cross-border healthcare travel.
Flight search integration
Frequently asked questions
Are DoctorBookly health tools free?
Yes. All medical calculators and reference tools on DoctorBookly are free to use in your browser. No account is required for most tools.
What free health tools and medical calculators are available?
DoctorBookly offers BMI, BMR, calorie, age, pregnancy due date, ideal weight, water intake, medication reminder, lab result guide, symptoms, conditions, glossary, and related wellness utilities — 16 tools on this hub.
Can these tools diagnose a medical condition?
No. Health tools are for general education only. They do not diagnose, treat, or replace advice from a licensed doctor, nurse, or pharmacist. In an emergency, call local emergency services.
Which formula does the BMI calculator use?
The BMI calculator uses the WHO standard: body mass index equals weight in kilograms divided by height in metres squared, then maps to international weight categories.
Does the calorie calculator use BMR and TDEE?
Yes. The calorie calculator estimates basal metabolic rate (BMR) with the Mifflin-St Jeor equation and adjusts for activity to estimate total daily energy expenditure (TDEE) for maintenance, loss, or gain goals.
Is the pregnancy calculator a medical diagnosis tool?
No. The pregnancy due-date and related calculators estimate dates for education and planning. Confirm pregnancy care and dates with a licensed clinician.
Do tools open on their own page?
Yes. Each card opens a dedicated tool page with the full calculator or reference — not only an on-page widget — so you can bookmark and share a clean URL.