Health · Visual BMI Analyzer

BMI Calculator

Interactive meter + color-coded classification | Instant health insights

Your Body Measurements

Height ft in or cm
Weight lbs or kg

About This BMI Calculator

This BMI Calculator estimates your Body Mass Index using your height and weight. It supports both imperial and metric inputs, automatically syncs equivalent units, and displays a visual BMI gauge with your category, healthy weight range, BMI Prime, and useful health insights.

How to Use

1. Enter Your Height — Use feet and inches, or enter height directly in centimeters.
2. Enter Your Weight — Use pounds or kilograms. The calculator automatically converts between units.
3. Click Calculate BMI — The result will show your BMI score and category.
4. Review the Gauge — The visual meter shows where your BMI falls from underweight to obesity.
5. Read the Insights — Check your healthy weight range, BMI Prime, and recommendation summary.

How It Works & Formula

BMI is calculated by dividing body weight in kilograms by height in meters squared. The same result can be calculated with pounds and inches using a conversion factor.

BMI = Weight (kg) / Height (m)2

Where:
• Weight = Your body weight in kilograms.
• Height = Your height in meters.
• BMI = Body Mass Index, a screening value used to classify weight ranges.

BMI = 703 × Weight (lb) / Height (in)2

Imperial Formula:
When using pounds and inches, multiply by 703 to get the standard BMI result.

Mathematical Expression

BMI = kg / m²

BMI = 703 × lb / in²

Example

Example: A person weighs 72.6 kg and is 1.70 m tall.

BMI = 72.6 / (1.70 × 1.70)
BMI = 72.6 / 2.89
BMI = 25.1

A BMI of 25.1 is usually classified as Overweight. BMI is a screening tool, so it should be interpreted with other health factors.

BMI Classification Table

Use this table as a quick reference for standard adult BMI categories.

CategoryBMI RangeGeneral Risk Level
UnderweightBelow 18.5Nutritional deficiency risk
Normal Weight18.5 – 24.9Lowest general risk
Overweight25.0 – 29.9Increased risk
Obesity Class I30.0 – 34.9High risk
Obesity Class II35.0 – 39.9Very high risk
Obesity Class III40.0 and aboveExtremely high risk

Note: BMI is a screening measurement and does not directly measure body fat percentage, muscle mass, or overall health.

Frequently Asked Questions

What does BMI mean? +
BMI stands for Body Mass Index. It is a simple ratio of weight to height used as a general screening tool for adult weight categories.
Is BMI accurate for everyone? +
BMI is useful for general screening, but it may not be accurate for athletes, very muscular people, pregnant individuals, older adults, or children. It does not directly measure body fat.
What is a healthy BMI range? +
For most adults, a BMI between 18.5 and 24.9 is considered the normal or healthy weight range.
Can I use pounds and inches? +
Yes. This calculator accepts feet, inches, and pounds, and it automatically syncs those values with centimeters and kilograms.
Should I rely only on BMI for health decisions? +
No. BMI should be used as a starting point. Waist size, body composition, blood pressure, activity level, diet, and medical history are also important.

Related Calculators & Resources

Body Fat Calculator Calorie Calculator Currency Converter Inflation Calculator Discount Calculator Log Calculator

Related Reading

• Understanding BMI Categories – What each BMI range means.
• BMI vs Body Fat Percentage – Why both measurements matter.
• Healthy Weight Range – How to interpret your result safely.
• Weight Management Basics – Simple habits for long-term health.

Understanding Your BMI

📌 BMI Categories (WHO)

Underweight: <18.5  |  Normal: 18.5–24.9
Overweight: 25–29.9  |  Obesity I: 30–34.9
Obesity II: 35–39.9  |  Obesity III: ≥40

🎯 How to Use

Enter height & weight in either metric or imperial. The colored gauge shows exactly where you fall, and the result card uses distinct colors for each category — making it instantly readable.