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Body Fat Calculator
Estimate body fat percentage with the US Navy tape-measure method, plus fat mass, lean mass and your ACE category.
BMI Calculator
Calculate adult body mass index (BMI) from height and weight, with the CDC weight category and healthy weight range.
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How to use this calculator
Enter your values after choosing the type of calculation in the tabs. The result updates as you type; press Calculate to confirm and jump to the result on mobile. Use Share to send the calculator with your result.
What is BMI?
Body mass index is weight in kilograms divided by height in meters squared. Health agencies use it to screen adults for weight categories that may relate to health risks.
BMI = weight (kg) ÷ height (m)²
BMI = 703 × weight (lb) ÷ height (in)²
Adult BMI categories (CDC)
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to < 25 | Healthy weight |
| 25 to < 30 | Overweight |
| 30 to < 35 | Obesity class 1 |
| 35 to < 40 | Obesity class 2 |
| 40 or more | Obesity class 3 (severe) |
Source: CDC, Adult BMI Categories.
Limits of BMI
- Muscular people can have a high BMI without excess fat.
- It doesn’t show where fat is stored; waist size adds useful information.
- Children and teens use BMI-for-age percentiles instead.
Frequently asked questions
What is a healthy BMI?
18.5 to less than 25 for adults, per the CDC.
How is BMI calculated in pounds and inches?
703 × weight (lb) ÷ height (in)².
About this tool
- Written by
- [Author: to be assigned]
- Reviewed by
- Expert review pending
- Last updated
- 31 Oct 2026
See our methodology and editorial policy. Think something’s off? Report an error with this tool.
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