BMI Calculator with the ADA Diabetes Screening Note
BMI = weight (kg) ÷ height (m)². A BMI of 70 kg at 1.75 m is 22.9. The ADA lists diabetes screening for adults with a BMI of 25 or higher (23 or higher for people of Asian ancestry) who have another risk factor. This tool shows your BMI and category. It sets no weight goals.
Calculate
Information only. For adults 20 and older; not for pregnancy. Nothing you type leaves your browser.
How it works
- Enter weight and height in kg and cm, or lb and inches.
- We apply the formula and the CDC adult categories.
- We add the ADA screening note if you are at or above the screening BMI.
CDC adult categories
| BMI (kg/m²) | Category |
|---|---|
| below 18.5 | Underweight |
| 18.5 to under 25 | Healthy weight |
| 25 to under 30 | Overweight |
| 30 or higher | Obesity |
CDC: for adults 20 and older the categories are the same regardless of age, sex or race.
BMI and diabetes screening
ADA Standards of Care 2026 (Table 2.5) list testing for diabetes or prediabetes in asymptomatic adults with a BMI of 25 or higher, or 23 or higher for people of Asian ancestry, who have one or more risk factors; for everyone else, testing begins at age 35. Only a lab test, ordered by a clinician, can diagnose either. See the A1C calculator to understand a result.
What BMI cannot tell you
BMI does not measure body fat directly or where it sits. It can mislead for very muscular people, older adults and others. Waist-to-height ratio adds another view. We do not offer weight-loss or calorie targets; if you want to talk about weight, your care team can help.
Frequently asked questions
How is BMI calculated?
Weight in kilograms divided by height in meters squared. In pounds and inches: 703 × weight ÷ height squared.
What are the BMI categories?
The CDC lists, for adults 20 and older: underweight below 18.5, healthy weight 18.5 to under 25, overweight 25 to under 30, and obesity 30 or higher.
Why does the ADA mention BMI 23 for Asian people?
The ADA lists testing for diabetes and prediabetes for adults with BMI 25 or higher, or 23 or higher for people of Asian ancestry, who have one or more risk factors. Without risk factors, testing begins at age 35.
Can BMI diagnose diabetes?
No. Only a lab test ordered by a clinician diagnoses diabetes or prediabetes. BMI is a screening number.
Does this give a weight goal?
No. We do not set weight-loss, calorie or BMI targets. Any goal is a conversation with your care team.
Information only, not medical advice. Your care team may set different targets for you, and only a lab test ordered by a clinician can diagnose diabetes or prediabetes. See our medical disclaimer.
Sources
- CDC: Adult BMI categories
- ADA Standards of Care in Diabetes—2026, Section 2: Diagnosis and Classification
Last reviewed: by the Diabetes Blogs editorial team. Information only, not medical advice.
