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BMI Calculator

Calculate your Body Mass Index (BMI).

cm
kg
cm

Health Risk Context

For adults, a larger waist circumference can indicate higher risk for heart disease and type 2 diabetes, even if BMI is normal. Your waist measurement is within a lower risk range.

Your BMI Score
24.2
Healthy Weight
1518.5253040+

1How to Use This Tool

  1. Enter your height in centimeters.
  2. Enter your weight in kilograms.
  3. Your BMI will calculate instantly, displaying your metric.

FAQFrequently Asked Questions

Q. What does BMI stand for?

BMI stands for Body Mass Index. It is a value derived from the mass (weight) and height of an individual to broadly categorize them.

Q. Is BMI accurate for everyone?

BMI is an approximation system. It may not be completely accurate for bodybuilders, highly muscular individuals, pregnant women, and the elderly.

Q. Why does age matter in BMI calculation?

For adults over 20, BMI limits remain static. For children and teens, BMI is compared against age and gender percentiles for accurate health monitoring.

Q. What is a healthy BMI range?

Generally, a healthy BMI range for normal adults is considered to be between 18.5 and 24.9.

Q. Does waist circumference affect BMI?

Waist circumference does not change the BMI number, but it is a critical secondary metric for determining the risk of metabolic and heart diseases.

Disclaimer: This tool is for informational purposes only and is not a substitute for professional medical advice. Always consult a healthcare provider for medical decisions.

The BMI Formula

Body Mass Index (BMI) evaluates body weight relative to height. Here are the standard formulas used in this calculator:

Metric System BMI = weight (kg) / [height (m)]²

Imperial System BMI = 703 × weight (lbs) / [height (in)]²

BMI Categories and Health Risks

The World Health Organization (WHO) has established the following BMI categories for adults (aged 20 and older). These categories help determine potential health risks associated with being underweight or overweight.

BMI Category

Range (kg/m²)

Health Risk Level

Underweight

< 18.5

Increased

Healthy Weight

18.5 – 24.9

Least

Overweight

25.0 – 29.9

Increased

Obese (Class I-III)

30.0+

High to Extremely High

While BMI is a useful screening tool, it does not directly measure body fat or metabolic health. Incorporating waist circumference measurements provides a more comprehensive view of overall risk.

Limitations and Weaknesses of BMI

Because BMI strictly calculates mass versus height, it can be mathematically inaccurate in specific physiological scenarios. Key weaknesses include:

  • Athletes and Bodybuilders: Individuals with high muscle mass weigh more, which can inaccurately classify them as overweight or obese despite having very low body fat percentages.
  • Older Adults: As we age, muscle mass typically declines and bone density may decrease. An older adult might have a "healthy" BMI but still carry an unhealthy high percentage of body fat.
  • Pregnancy: Pregnant individuals naturally gain weight, stripping the index of any diagnostic value regarding body fat health risks during this time.
  • Metabolism Variations: Your basal metabolic rate (BMR) also plays a vast role in how bodies manage energy and fat.

Data Privacy Notice

Your health data is highly personal. This BMI calculator executes entirely within your browser window. No physical measurements, inputs, or generated health outcomes are transmitted to or stored on our servers.

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