BMI Calculator

This BMI calculator works out your Body Mass Index from your height and weight, giving you a quick screening figure that doctors and health services use to flag whether your weight sits in a healthy range for your height. Choose metric or imperial units: enter your height in metres and weight in kilograms, or your height in feet and inches and weight in stones, pounds and ounces. The calculator divides your weight by the square of your height and returns your BMI score instantly, along with the healthy weight range for your exact height, shown in kilograms or in stone, pounds and ounces depending on which units you used. It also highlights which of five categories your result falls into: underweight (under 18.5), healthy weight (18.5 to 24.9), overweight (25 to 29.9), obese (30 to 39.9) or morbidly obese (40 and over), so you can see at a glance where you stand. Use it to track changes over time, set a realistic weight target, or understand a number your doctor or gym has mentioned. BMI is a simple ratio that does not measure body fat, muscle mass or where fat is carried, so it can be misleading for athletes, older adults, pregnant women and some ethnicities. Treat the result as general information only, not a diagnosis, and talk to your doctor about what a healthy weight looks like for you.

General information, not medical advice. BMI is a rough screening measure and does not account for muscle, body composition, ethnicity, age or pregnancy. It can misclassify athletes, older adults and some ethnic groups, and it is not applied to children the same way. Talk to your doctor about what a healthy weight means for you.

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