BMI Calculator

Enter your height and weight in metric or imperial units to see your Body Mass Index and the WHO category it falls into.

Height (cm)Weight (kg)

22.9

Healthy

How to use BMI Calculator

1Switch between metric (cm / kg) or imperial (ft, in / lb).
2Enter height and weight.
3Read your BMI and category.

Features

Metric and imperial units
WHO category labels
Visual range indicator
Healthy weight range for your height

Common use cases

Tracking weight progress over time
Initial fitness assessment
Filling medical or insurance forms
Comparing against WHO healthy ranges

Why use Synctoolo's BMI Calculator?

BMI is a quick screening tool, useful as a starting point but never a full picture of health. Our calculator shows the result with context, not just a number.

Guide: BMI Calculator

Understanding BMI and its limits

Body Mass Index divides weight by height squared to place adults in broad categories: underweight, healthy weight, overweight and obese. Health organisations use it as a population screening tool because it is fast and requires only two measurements.

BMI does not distinguish muscle from fat. Athletes with low body fat often score overweight. It also does not account for age, sex or ethnicity. Use BMI as one data point, not a complete health diagnosis. Consult a medical professional for personalised advice.

Frequently asked about BMI Calculator

Is BMI accurate for athletes?+

Not very. Muscle is denser than fat, so athletes often score in the 'overweight' range despite low body fat. Use body-composition measurements for a fuller picture.

What BMI is considered healthy?+

The WHO defines 18.5 to 24.9 as the healthy range for adults. Below 18.5 is underweight, 25–29.9 is overweight and 30+ is obese.

Does BMI work for children?+

Not directly. Children use age- and sex-specific BMI percentiles. Our calculator targets adults aged 20 and over.

Why is BMI criticised?+

It doesn't distinguish fat from muscle, doesn't account for fat distribution, and was developed from data on European men. Treat the result as one data point, not a diagnosis.

More Calculators

View all →