Anorexic BMI Calculator
Enter height and weight to get your BMI and its CDC adult category, where under 18.5 counts as underweight. The result stops there. It does not show the DSM-5 severity levels for anorexia nervosa. Those are listed in the formula section below for reference. A BMI is a screening number, not a diagnosis.
How to use the Anorexic BMI Calculator
- Enter your numbers in the Anorexic BMI Calculator above.
- Press the Calculate BMI button to see the result.
- To try other numbers, change any value and press the button again.
The clinical BMI thresholds
BMI = Weight (kg) / Height (m)² · · · DSM-5 severity: Mild ≥17, Moderate 16–16.99, Severe 15–15.99, Extreme <15
BMI alone does not diagnose anorexia. DSM-5 also requires restricted food intake, an intense fear of gaining weight and a disturbed view of one's own body. A clinician uses the severity levels above only after making the diagnosis, and the BMI cut-offs are for adults. The calculator shows the CDC category, not these levels.
Worked example
An adult who is 5'6" and weighs 95 lb has a BMI of 95 / 66² × 703 ≈ 15.33, which the calculator labels Underweight. On the DSM-5 scale above, 15.33 falls in the 15 to 15.99 band that DSM-5 calls severe. That band only applies once a clinician has diagnosed anorexia, so a BMI like this is a reason to see a doctor, not a label to apply to yourself.
Frequently asked questions
Is low BMI sufficient for diagnosis?
No. DSM-5 requires three criteria: significantly low weight, intense fear of gaining weight, and disturbed self-perception. Some patients with anorexia have higher BMIs (atypical anorexia).
When should I get professional help?
Now, if you or someone you know has a BMI under 17.5, is cutting back on food on purpose, or feels anxious about eating. A family doctor is a good first step. In a crisis in the US, call or text 988.
Does the result show the DSM-5 severity level?
No. The result shows your BMI and its CDC category, such as Underweight below 18.5. To see where a BMI sits on the DSM-5 scale, compare it with the formula section: 17 or more is mild, 16 to 16.99 moderate, 15 to 15.99 severe and under 15 extreme. The calculator does not assess anyone for an eating disorder. Only a qualified clinician can, so talk to one about any concern.