Health Calculators
Free health calculators BMI, calorie needs, and more, instantly in your browser.
BMI Calculator
Calculate your Body Mass Index instantly.
Calorie Calculator
Find your daily calorie needs based on activity level.
BMR Calculator
Find your Basal Metabolic Rate and daily calorie needs.
Body Fat Calculator
Estimate your body fat percentage using the US Navy method.
Ideal Weight Calculator
Find your estimated ideal body weight based on height and sex.
Calories Burned Calculator
Estimate calories burned for walking, running, cycling, and more.
Macro Calculator
Find your daily protein, carb, and fat targets based on your calorie goal.
Sleep Calculator
Find the best bedtime or wake-up time based on 90-minute sleep cycles.
Choosing and using health calculators
Health calculators can provide useful planning estimates, but a formula cannot account for every difference in body composition, medical history, medication, pregnancy, disability, or athletic training. Each calculator explains its method and assumptions so you can interpret the number as a general reference rather than a diagnosis.
Tips for reliable results
Use consistent measurements and compare trends over time instead of treating a single result as a verdict. If a result affects eating, exercise, sleep, or healthcare decisions, discuss it with a qualified professional who can consider your full circumstances. Seek urgent medical care for concerning symptoms rather than relying on an online calculator.
Choose a tool above to see its inputs, method, privacy notes, examples, limitations, and answers to common questions. Related tools are linked on every page so you can continue a task without returning to search.