AI Calculator Tool

BMI Calculator – Body Mass Index

Free BMI calculator: height + weight → Body Mass Index and category chart. Adults 18+. Not medical advice.

BMI Chart

CategoryBMI Range
Severe Thinness0 - 16
Moderate Thinness16 - 17
Mild Thinness17 - 18.5
Normal18.5 - 25
Overweight25 - 30
Obese Class I30 - 35
Obese Class II35 - 40
Obese Class III40 -

Welcome!

Enter your height and weight to get your Body Mass Index (BMI) and see which category you fall into. The same formula applies to men and women; this is a screening tool, not a diagnosis.

What is BMI?

BMI, or Body Mass Index, is a quick way to check if you're in a healthy weight range for your height. It's used by doctors and health experts worldwide, including the CDC and WHO, to screen for weight categories that may lead to health problems. The calculation and categories are the same for men and women.

How to Calculate BMI

BMI is easy to figure out. Here's how:

  • Metric Units: BMI = weight (kg) / [height (m)]²
  • US Units: BMI = 703 × weight (lbs) / [height (in)]²

BMI Categories (Adults)

ClassificationBMI Range (kg/m²)
Severe Thinness< 16
Moderate Thinness16 - 17
Mild Thinness17 - 18.5
Normal18.5 - 25
Overweight25 - 30
Obese Class I30 - 35
Obese Class II35 - 40
Obese Class III> 40

Why does BMI matter?

Knowing your BMI can help you spot if you're at risk for health issues like heart disease, diabetes, or high blood pressure. It's a great first step toward a healthier you!

A quick tip:

BMI is a helpful tool, but it doesn't tell the whole story. Muscle, age, and body type all play a part. For a full picture of your health, chat with your doctor.

Frequently Asked Questions

FAQs
  • Is BMI the same for men and women?
    Yes! For adults, BMI is calculated the same way for everyone. But remember, it doesn't account for muscle or body composition.
  • What is a healthy BMI?
    A BMI between 18.5 and 25 is considered healthy for most adults, according to the CDC and WHO.
  • Where can I learn more?
    Check out resources from the CDC (cdc.gov) or the World Health Organization (who.int) for more details on BMI and health.