BMI Calculator
Understanding the US Standard BMI Calculator
The Body Mass Index (BMI) is a widely used screening tool in the United States healthcare system. By comparing your weight in relation to your height, our BMI calculator provides a quick estimate of your total body fat. While it isn't a diagnostic tool, it is the standard metric used by doctors to assess whether you fall into a healthy weight category.
How is BMI Calculated?
The standard mathematical formula for BMI using US customary units (pounds and inches) is:
BMI = [Weight (lbs) / Height (inches)²] × 703
Our tool automates this complex math, providing you with an instant reading and placing you into one of the standard categories defined by the Centers for Disease Control and Prevention (CDC).
BMI Categories
- Underweight: BMI less than 18.5
- Normal Weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obese: BMI of 30 or greater
Frequently Asked Questions
Is BMI accurate for everyone?
No. BMI is a general screening tool and does not differentiate between muscle mass and fat mass. Bodybuilders or highly athletic individuals may be classified as "overweight" or "obese" despite having very low body fat.
Can children use this BMI calculator?
Standard BMI categories are only for adults ages 20 and older. For children and teens, BMI is age- and sex-specific and requires a different percentile-based calculation.
What should I do if my BMI is high?
A high BMI suggests an increased risk for conditions like heart disease, high blood pressure, and type 2 diabetes. You should consult with a healthcare provider for a comprehensive health assessment.