Weight & Body Composition Calculators
Understand your weight beyond the number on the scale — how much is fat and muscle, where you carry it, and what a healthy target looks like for you.
How to use these calculators
Your weight alone says little about your health. Two people can weigh the same yet have very different amounts of muscle and body fat, and very different risks depending on whether fat sits around the waist or the hips. These free calculators look at your body from several angles. Start with BMI (with Asian cut-offs) for a quick screen, then check where you carry fat with the waist-to-height ratio, waist-to-hip ratio or the newer Body Roundness Index. To see what your weight is made of, use the body fat and lean body mass calculators.
When you are ready to set a goal, the ideal weight calculator shows a healthy range for your height, and the weight loss and weight gain calculators give realistic timelines that account for your metabolism changing as you go. Parents can check children’s growth with the child BMI calculator.
Frequently asked questions
Which is better: BMI, body fat or waist measurements?
Each tells you something different. BMI is a quick screen, body fat shows composition, and waist measurements show belly fat, which is most closely linked with diabetes and heart disease. Using BMI plus a waist measure gives the best simple picture.
How often should I check these numbers?
Every 2–4 weeks is enough. Weight and waist change slowly, and daily changes are mostly water.
Are these calculators accurate for everyone?
They are designed for healthy adults (except the child BMI calculator). Results are estimates and are less accurate for athletes, older adults and during pregnancy.
More health calculators
Turn your numbers into a real plan
Dr. Rida Saeed builds personalised, culturally familiar meal plans around your results, health history and routine — fully online.
Chat on WhatsAppSee custom diet plansMedical disclaimer: These calculators give general estimates for education only and are not a diagnosis or a substitute for advice from your doctor or a registered dietitian. Read our full medical disclaimer.