What is BMI and how is it calculated?

BMI (Body Mass Index) is a measure of body fat based on height and weight. For metric: BMI = weight(kg) / height(m)². For imperial: BMI = 703 × weight(lb) / height(in)². A BMI of 18.5-24.9 is considered normal.

What are the BMI categories?

Underweight: BMI < 18.5. Normal weight: BMI 18.5-24.9. Overweight: BMI 25-29.9. Obese: BMI ≥ 30. These categories are based on WHO standards and help assess health risks associated with weight.

Is BMI accurate for everyone?

BMI is a useful screening tool but has limitations. It doesn't distinguish between muscle and fat, so athletes may have high BMI but low body fat. It may also be less accurate for elderly people, children, and certain ethnic groups. Consider other measures like waist circumference for a complete assessment.

What is the ideal BMI range?

The ideal BMI range is 18.5 to 24.9. This range is associated with the lowest risk of chronic diseases. However, the 'ideal' can vary based on age, ethnicity, and individual health factors. Consult a healthcare provider for personalized advice.

How do I calculate my ideal weight?

The calculator shows your ideal weight range based on BMI 18.5-24.9 for your height. For example, at 175 cm, ideal weight is 56.7-76.2 kg. This gives you a target range to aim for.

Is my health data sent to a server?

No. All calculations happen entirely in your browser using JavaScript. Your weight, height, and BMI results are never transmitted over the network. The tool works offline after the page loads.

Tools

Weight (kg)

Height (cm)

Your BMI

22.9

BMI Calculator — Calculate Body Mass Index & Health Status

Free BMI calculator to calculate your Body Mass Index. Supports both metric (kg/cm) and imperial (lb/ft-in) units. Instantly shows BMI category and health risk assessment. All calculations run locally in your browser.

Features

✓Calculate Body Mass Index (BMI) instantly
✓Support metric units (kilograms and centimeters)
✓Support imperial units (pounds and feet/inches)
✓Show BMI category (underweight, normal, overweight, obese)
✓Display health risk assessment for your BMI
✓Calculate ideal weight range for your height
✓Switch between metric and imperial units
✓Instant calculation as you type
✓Based on WHO BMI classification standards
✓All calculations run locally in your browser

How to Use

1Choose your preferred unit system (metric or imperial).
2Enter your weight (kg or lb).
3Enter your height (cm or feet/inches).
4View your BMI result instantly.
5Check your BMI category and health risk assessment.
6See your ideal weight range for reference.

Frequently Asked Questions

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