You want a quick adult height-to-weight screening reference and understand that body composition is not measured directly.
BMI Calculator
Calculate adult body mass index from height and weight locally in your browser.
Start here
Choose US customary or metric units.
Browser-first
Your height and weight values are calculated locally in your browser and are not uploaded to a server.
Useful for
Check a quick adult BMI reference
Measurement units
BMI value22.5
Adult BMI categoryHealthy range
BMI is a general adult reference and does not replace medical or nutrition advice.
Quick answer
Calculate adult BMI from height and weight
Enter height and weight in US customary or metric units to calculate body mass index and compare the result with standard adult screening categories.
BMI is not a diagnosis and is not designed for children, pregnancy, or every athletic, medical, or body-composition context.
BMR Calculator: Estimate basal metabolic rate with the Mifflin-St Jeor formula locally in your browser.
About this tool
Calculate adult body mass index from height and weight locally in your browser.
Your height and weight values are calculated locally in your browser and are not uploaded to a server.
Health information notice
BMI is a general adult screening reference, not a medical diagnosis. It may be misleading for athletes, older adults, pregnancy, minors, or people with medical conditions. Consult a qualified professional for personal health decisions.
How to use it
- Choose US customary or metric units.
- Enter height and weight.
- Review the BMI value, adult category, formula, and limitations.
Common use cases
- Check a quick adult BMI reference
- Compare height and weight ranges
- Use BMI as a starting point before deeper health planning
Adult BMI Categories
BMI is a quick body-size reference based only on height and weight. It does not measure body fat, muscle mass, waist size, or health status.
| BMI range | Common adult category | Important limitation |
|---|---|---|
| Below 18.5 | Underweight | May need professional review if paired with fatigue, appetite changes, or rapid weight loss. |
| 18.5 to below 25 | Healthy range | Still does not describe body composition or metabolic health by itself. |
| 25 to below 30 | Overweight | Use waist, activity, health history, and professional guidance for context. |
| 30 and above | Obesity range | A screening signal, not a diagnosis by itself. |
BMI Formula and US-Unit Example
The calculator accepts either US customary or metric measurements and converts them to the same BMI value. In metric units, BMI is weight in kilograms divided by height in meters squared. With pounds and inches, the equivalent formula multiplies by 703.
| Step | Example | Result |
|---|---|---|
| Enter height | 5 ft 8 in (68 in) | Use the full height in inches. |
| Enter weight | 150 lb | Keep the measurement reasonably current. |
| Calculate | 150 / 68² x 703 | BMI is about 22.8. |
| Interpret | 22.8 | Falls in the common adult healthy range of 18.5 to below 25. |
What BMI Can and Cannot Tell You
| Question | BMI helps? | Useful next context |
|---|---|---|
| Is my weight high or low relative to height? | Yes, as an adult screening reference | Review the category and trend over time. |
| What is my body-fat percentage? | No | BMI does not separate fat, muscle, and bone. |
| Does this diagnose a health condition? | No | Use medical history, examination, and professional advice. |
| What should I calculate next? | Not by itself | Use BMR or TDEE only when an energy estimate is the real question. |
FAQ
Is BMI a diagnosis?
No. BMI is a broad screening reference and cannot diagnose health status or body composition.
Does BMI work for everyone?
No. It can be less useful for athletes, pregnancy, minors, older adults, and special health conditions.
Are my measurements uploaded?
No. The calculation runs locally in your browser.