- Choose your units — metric (centimetres and kilograms) or imperial (feet and pounds).
- Enter your height and weight and press Calculate.
- Your BMI is your weight in kilograms divided by the square of your height in metres.
- You get your BMI value, your weight category, the full category table and the healthy weight range for your height.
Home › BMI Calculator
BMI Calculator — Check Your Body Mass Index
Enter your height and weight to find your BMI in seconds. Works in metric (cm/kg) and imperial (feet/lbs) units, and shows your weight category plus the healthy weight range for your height.
How the BMI calculator works
Frequently asked questions
What is a healthy BMI range?
A BMI between 18.5 and 24.9 is considered healthy for most adults. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or above falls in the obese range.
Is BMI accurate for athletes?
Not entirely. BMI cannot tell muscle from fat, so very muscular people can score 'overweight' while being perfectly healthy. It's a useful general screening tool, not a diagnosis — for body composition ask a professional.
What is the BMI formula?
BMI = weight in kilograms divided by height in metres squared (kg/m²). In imperial units the same result comes from 703 × pounds / inches².
Does BMI differ for men and women?
The BMI categories are the same for adult men and women. Children and teenagers use age- and sex-specific percentile charts instead of the adult ranges.
Estimates are for guidance only and are based on published 2025/2026 rates. Always confirm with a qualified professional for financial decisions.