Free FFMI Calculator
Estimate fat-free mass index and height-normalized FFMI from weight, height and body-fat percentage.
FFMI Calculator
Enter a value to begin.
How to use this ffmi calculator
- Enter adult height, weight and a separately measured or estimated body-fat percentage.
- Check the inputs and preview, then use the primary action.
- Download, copy or use the result shown by the tool.
How the result is calculated
Fat-free mass is weight multiplied by one minus body-fat fraction. FFMI divides that mass by height squared; normalized FFMI adjusts to 1.8 metres. It is an educational body-composition estimate, not a diagnosis or performance assessment.
Method source: Original fat-free mass index study.
All calculation and transformation work happens in this browser tab. No entered value is sent to an Noler Tools application server.
Important limitations
Results are provided for convenience and should be checked independently before an important decision. A format or checksum result never authenticates an identity, document, account, licence, vehicle or registration.
Health limitation: This is a general educational estimate, not medical advice, diagnosis or a substitute for care from a qualified clinician. Do not use it to make treatment, nutrition, pregnancy or emergency-care decisions.
Frequently asked questions
Is this ffmi calculator free?
Yes. It is free to use and does not require an account.
Does Noler Tools save my input?
No. The input and result remain in temporary browser memory and are not uploaded or saved by this site.