Health & FitnessFormula-based · Runs in your browser

Low BMI Screening Calculator

Calculate adult BMI and show low-BMI screening ranges without diagnosing an eating disorder.

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Calculation steps

Follow what happened from the selected formula to the displayed answer.

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  1. 1

    Formula selected

    The calculator uses the following formula or method.

    BMI = weight in pounds ÷ height in inches² × 703; the result is mapped to adult thinness and healthy-weight screening ranges.

  2. 2

    Values entered

    Your values are placed into the calculation.

    Enter values to see what is used in this step.

  3. 3

    Result calculated

    The formula or method produces the following result values.

    Results will appear after a successful calculation.

  4. 4

    Answer formatted

    Displayed values are rounded and formatted using each output’s configured precision.

Scenario comparison

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Data and privacy

How it works

This page keeps its older URL for compatibility, but the calculator is a low BMI screening calculator. It calculates adult BMI and shows low-BMI screening ranges. It does not diagnose anorexia nervosa or any other condition.

Input query strings and outputs

Use an input name in this page’s URL as ?name=value, and join additional inputs with &. Portable shared links may instead use the compact ?ac= state parameter.

Input query strings

3
  • ?heightFt= Height (ft)

    Number · Optional · Default: 5

  • ?heightIn= Height (in)

    Number · Optional · Default: 6

  • ?weight= Weight (lbs)

    Number · Optional · Default: 100

Outputs

1
  • result Result

    Text · Primary output

result contains the calculator’s complete rendered result area, including its visible result cards, tables, charts, and messages.

Formula

BMI = weight in pounds ÷ height in inches² × 703

Displayed ranges

  • Below 16: severe thinness range
  • 16 to below 17: moderate thinness range
  • 17 to below 18.5: mild thinness / underweight range
  • 18.5 to below 25: healthy-weight screening range

Important

BMI is only a screening measure. An eating-disorder diagnosis requires a qualified clinician and cannot be made from BMI alone. Seek care for rapid weight loss, fainting, weakness, food restriction, purging, or distress about eating or weight.

Sources
Limitations
  • BMI alone cannot diagnose an eating disorder, malnutrition, or another condition. Seek qualified care for concerns about eating or weight.
  • Health results are educational estimates, not a diagnosis or treatment recommendation. Individual circumstances may require a qualified clinician's assessment.