ELIFIT

Body composition tool

BMI Calculator

Calculate body mass index, understand what the number can—and cannot—tell you, and use it as one small piece of a broader health picture.

Understanding your BMI

Body Mass Index (BMI) is a simple ratio of your weight to your height, used around the world as a quick screening number. It places your weight into one of four broad bands so you can see, at a glance, whether it sits in the range linked to lower health risk for most people.

How to use it

  1. 1Enter your height in centimetres and your weight in kilograms.
  2. 2Select Calculate to see your BMI and its category on the scale.
  3. 3Read the healthy weight range shown for your height.
  4. 4Re-check every few weeks so you follow the trend, not a single reading.

How it helps your fitness

BMI gives you a fast, free starting point for a weight goal and a number you can track over months to confirm a plan is working. Watching it trend down during a fat-loss phase, or hold steady while you build muscle, tells you more than any single reading.

What the numbers mean

BMI value
Your weight in kilograms divided by your height in metres squared (kg/m²).
Underweight — below 18.5
Below the typical healthy range; often a sign you need more energy and protein.
Normal — 18.5 to 24.9
The band linked to the lowest health risk for most adults.
Overweight / obese — 25 and above
Above the typical range; 30 and over is classed as obese.

Keep in mind

BMI cannot tell muscle from fat or show where fat is stored, so very muscular people often read high. Use it alongside your waist measurement, how your clothes fit, and advice from a clinician rather than as a diagnosis.