BMI Calculator
Body Mass Index (BMI) is a quick screening measure used by doctors across the United States to categorize weight relative to height. Enter your height and weight in pounds and feet/inches or metric units to see your BMI instantly.
Alongside your score you get your CDC weight category and the healthy weight range for your height, so you know exactly where you stand.
Your BMI
23.6 Healthy weight
- Healthy weight range for your height
- 125–169 lb
Underweight
Healthy
Overweight
Obesity
How the BMI Calculator works
The calculation follows the standard method used across the US — no shortcuts, no hidden assumptions. Here is exactly what happens behind the scenes:
Formula
BMI = weight (kg) / height² (m)
- Convert height to meters and weight to kilograms if using US units.
- Square the height in meters, then divide weight by that value.
- Compare the result to CDC adult categories (see below).
Frequently Asked Questions
What are the official BMI categories?
For adults the CDC uses: below 18.5 underweight, 18.5–24.9 healthy weight, 25.0–29.9 overweight, and 30.0+ obesity. The same ranges apply to adult men and women.
Is BMI accurate for athletes or older adults?
No single number fits everyone. BMI does not distinguish muscle from fat, so muscular athletes may register as overweight, while older adults with lost muscle mass may look healthy. Treat BMI as a first screening step, not a diagnosis.
How do I find my healthy weight range?
Multiply your height in meters squared by 18.5 and by 24.9 — that span is the weight range classified as healthy. The calculator shows it converted back to pounds for you.
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