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BMI Calculator

Calculate your Body Mass Index using metric or imperial units. This is a screening calculation — not a diagnosis.

Your measurements are calculated entirely in your browser. Nothing is stored, sent, or tracked.

How BMI is calculated

BMI is a simple formula using your weight and height:

Metric

BMI = kg / m²

Example: 65 kg, 170 cm → 65 / (1.7)² = 22.5

Imperial

BMI = 703 × lb / in²

Example: 150 lb, 5 ft 7 in → 703 × 150 / 67² = 23.5

What the result means

The standard adult BMI categories are:

UnderweightBelow 18.5
Normal weight18.5 – 24.9
Overweight25.0 – 29.9
Obese30.0 and above

These categories are widely used reference ranges. They do not alone determine health status.

Limitations of BMI

BMI is a useful starting point but has well-known limitations. It does not:

  • Measure body fat percentage or distribution.
  • Distinguish between muscle and fat mass — people with high muscle mass (e.g., athletes) may register as overfat at a normal BMI.
  • Account for age-related changes in body composition. Older adults may carry more fat at the same BMI as younger adults.
  • Apply standard thresholds to children and adolescents — they use age- and sex-specific growth charts.
  • Accommodate pregnancy, where weight gain is expected.
  • Reflect ethnic or genetic differences in body composition.

Planning medical travel to India

If you are considering treatment in India, understanding your general health metrics can be part of preparing for a consultation with a hospital or specialist. BMI is one data point a doctor may consider alongside medical history, blood work, and imaging.

Medi In India can help you connect with accredited hospitals and specialists who can provide a proper clinical assessment. We coordinate the logistics of your medical journey — from finding the right provider to arranging travel and accommodation.

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Medical Disclaimer: This BMI calculator is for general informational purposes only. It does not constitute medical advice, diagnosis, or treatment recommendations. Medi In India is a medical tourism facilitator and does not provide clinical services. Always consult qualified healthcare professionals for medical decisions.

Frequently Asked Questions

What does BMI stand for?+
BMI stands for Body Mass Index. It is a number calculated from your weight and height. It is used as a simple screening tool to categorise weight status, but it is not a diagnostic measure.
How is BMI calculated?+
For metric units: divide your weight in kilograms by the square of your height in metres (kg per m squared). For imperial units: multiply your weight in pounds by 703, then divide by the square of your height in inches (703 times lb per in squared).
Is BMI a diagnosis?+
No. BMI is a screening calculation. It does not measure body fat directly, nor does it account for factors like muscle mass, bone density, age, sex, or ethnicity. A healthcare professional can provide a proper assessment.
Does BMI apply to children?+
The standard adult BMI categories used here (underweight, normal, overweight, obese) are generally for adults aged 20 and older. Children and adolescents use age- and sex-specific BMI percentiles.
Why might BMI not be accurate for me?+
BMI does not distinguish between fat mass and muscle mass. Athletes and people with high muscle mass may have a high BMI without excess body fat. Pregnancy, age, and certain medical conditions also affect the reliability of BMI as a health indicator.
Is my data stored when I use this calculator?+
No. All calculation happens locally in your browser. No measurements, results, or personal data are sent to any server, stored in cookies, or saved in local storage.