Body mass index

Fitness / FREE CALCULATOR

Calculate adult BMI as a screening measure; it is not a diagnosis and is unsuitable for children or pregnancy.

Enter your numbers

READY WHEN YOU ARE

Your answer starts here.

Enter your values and select Calculate to see the result and any available breakdown.

How to use this calculator

  1. Enter weight (kg). Use the unit shown beside the field.
  2. Enter height (cm). Use the unit shown beside the field.
  3. Select Calculate and review the result. Select Reset to restore the example inputs.

How the calculation works

BMI = weight/(height/100)^2.

Worked example

Entering 80 and 200 gives a primary result of 20.

Understand your result

Use this result together with the worked example and the assumptions below. Calculate adult BMI as a screening measure; it is not a diagnosis and is unsuitable for children or pregnancy.

Assumptions and limitations

Calculate adult BMI as a screening measure; it is not a diagnosis and is unsuitable for children or pregnancy. Check units and assumptions before using the result in a decision. Results are rounded for display.

Questions about this tool

What does this tool calculate?

Calculate adult BMI as a screening measure; it is not a diagnosis and is unsuitable for children or pregnancy.

What should I check before using the answer?

Calculate adult BMI as a screening measure; it is not a diagnosis and is unsuitable for children or pregnancy. Check units and assumptions before using the result in a decision.

Related guides

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