BMI Calculator
Calculate your Body Mass Index (BMI) using metric (kg/cm) or imperial (lbs/inches) measurements. Instantly see your WHO weight category. Free, private, and runs entirely in your browser with no uploads.
Key Capabilities
What is BMI?
Body Mass Index (BMI) is a value derived from a person's weight and height. It is used as a screening tool to categorise adults as underweight, normal weight, overweight, or obese. BMI does not directly measure body fat.
What are the WHO BMI categories?
Underweight: BMI below 18.5. Normal weight: 18.5–24.9. Overweight: 25–29.9. Obese: 30 or above. These classifications apply to adults aged 18 and over.
Is BMI accurate for everyone?
BMI is a useful population-level screening tool but has known limitations. It does not account for muscle mass, bone density, age, sex, or fat distribution. Athletes may show high BMI due to muscle. Always consult a doctor for a comprehensive health assessment.
Is my data private?
Yes. All BMI calculations run locally in your browser using JavaScript. No personal data, weight, or height values are ever sent to any server.
How to Use
Upload your medical document
Open the BMI Calculator tool and upload your medical document (prescription, lab report, or medical record). Your data stays in your browser — zero server uploads.
AI analysis begins
The tool analyzes your document using specialized medical OCR models trained on healthcare documents. This typically takes 3-8 seconds.
Review extracted information
Review the structured medical information extracted from your document. Copy results or download for your records.
Frequently Asked Questions
What is BMI?
Body Mass Index (BMI) is a value derived from a person's weight and height. It is used as a screening tool to categorise adults as underweight, normal weight, overweight, or obese. BMI does not directly measure body fat.
What are the WHO BMI categories?
Underweight: BMI below 18.5. Normal weight: 18.5–24.9. Overweight: 25–29.9. Obese: 30 or above. These classifications apply to adults aged 18 and over.
Is BMI accurate for everyone?
BMI is a useful population-level screening tool but has known limitations. It does not account for muscle mass, bone density, age, sex, or fat distribution. Athletes may show high BMI due to muscle. Always consult a doctor for a comprehensive health assessment.
Is my data private?
Yes. All BMI calculations run locally in your browser using JavaScript. No personal data, weight, or height values are ever sent to any server.
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