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Health & fitness

BMI Calculator

Calculate adult body mass index from metric height and weight.

Understand the limitations belowMeasurements stay on this device

Your measurements

Runs on your device

YOUR ESTIMATE

Your result

Let’s calculate.

Use the Calculate button to see your result.

An estimate, not a diagnosis.

How to use this tool

  1. Enter weight, height.
  2. Select Calculate to view the result.
  3. Check the method and assumptions below before using the result.

The method, explained

BMI = weight in kilograms ÷ height in meters squared. CDC adult categories: below 18.5, underweight; 18.5 to below 25, healthy weight; 25 to below 30, overweight; 30 or above, obesity.

A WORKED EXAMPLE

At 70 kg and 175 cm, BMI is approximately 22.86, within the CDC adult healthy-weight range.

What to keep in mind

For adults aged 20 and older only. BMI does not directly measure body fat and may be misleading during pregnancy or for people with high muscle mass. It is not a diagnosis.

Reference: CDC adult BMI categories

Common questions

Is BMI a measure of body fat?

No. BMI relates weight to height and is a screening measure. Body composition and other health factors need separate assessment.

Can this be used for children?

No. Children and teens need age- and sex-specific growth references rather than these adult ranges.

Methodology maintained by ClarityKit. How these tools are built and checked.