What is BMI and why is it important?

BMI (Body Mass Index) is a measure of body fat based on height and weight. It helps identify whether you’re underweight, healthy, overweight, or obese. Doctors often use BMI to assess health risks related to weight.

Is BMI accurate for everyone?

BMI is a useful screening tool, but it doesn’t account for muscle mass, body fat percentage, or distribution. Athletes, seniors, and children may need additional measures like body fat testing or waist-to-hip ratio.

What is a healthy BMI range?

For adults, a BMI between 18.5 and 24.9 is considered healthy. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or higher is obese.

How do I calculate BMI manually?

The formula is BMI = weight (kg) ÷ height (m²). For pounds/inches: BMI = (weight in lbs ÷ height in inches²) × 703.

How often should I check my BMI?

It’s recommended to check your BMI every few months or when your weight changes significantly, especially if you’re monitoring health or fitness progress.

BMI Calculator

Real-time BMI, metric & imperial conversion, tracking, export and accessibility features.

Theme

Translate

Enter your details — results update instantly as you type. Toggle units to switch measurement system; values will auto-convert.

Mode

Sex

Age (years)

Units

Height

Tip: enter cm or m — tool will prefer the most precise non-empty field.

Weight

Waist circumference (optional)

Activity level (optional)

Body type (optional)

Your BMI

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BMI position

Under
<18.5

Healthy
18.5–24.9

Over
25–29.9

Obese
≥30

Target healthy weight range for your height:

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Visualize BMI (trend & comparison)

Storage:

Local only. Not stored unless you save.

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