Health Calculator

BMI CALCULATOR

Check Body Mass Index with ideal-weight range, BMI Prime and waist-to-height ratio.

Private by design No signup · Free

Your Details

Your Result

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Enter your details

Healthy range

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BMI Prime

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Waist / height

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Est. body fat

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BMI is a screening estimate, not a diagnosis. Athletes, children, pregnant users and older adults should interpret results with a clinician.

Health screening estimates for education only — not medical advice. Interpret with a qualified clinician. Disclaimer

Frequently Asked Questions

What is BMI and what does my result mean?

BMI is Body Mass Index, a weight-to-height screening estimate. Under 18.5 suggests underweight, 18.5 to 24.9 healthy range, 25 to 29.9 overweight, and 30 or above obesity range for adults.

How do I check ideal weight for my height?

Enter height, age and gender to see the healthy BMI weight range beside your result. Ideal weight keeps BMI between 18.5 and 24.9, calculated in metric or imperial units without signup.

Is BMI different for kids and athletes?

Yes. For kids BMI is compared as an age-and-gender percentile rather than adult cutoffs. For muscular athletes, BMI Prime and waist-to-height ratio add context since muscle weighs more than fat.

What is waist-to-height ratio and BMI Prime?

Waist-to-height ratio is waist divided by height, with lower values indicating less central fat. BMI Prime is BMI divided by 25, so 1.0 means at the limit and below 1.0 is within range.

Can I use metric and imperial units?

Yes. Switch between kilograms with centimeters or pounds with feet and inches. The converter applies the correct formula including the 703 factor for imperial, updating results immediately.

How is body fat estimated from BMI?

Body fat from BMI is an estimate from BMI value, age and gender, not a direct measurement. It tracks general trends alongside waist ratio. For precise percentage use clinical methods instead.

How to Use

Enter age, gender, height and weight

Choose metric or imperial units and fill in measurements with age and gender.

Add waist for extra ratio

Optionally enter waist circumference for waist-to-height ratio alongside BMI.

Review BMI and charts

See BMI value, Prime, category, ideal-weight range and adult chart guidance.

Compare and plan

Adjust target weight to stay within healthy range and track changes over time.

How to Calculate

BMI equals weight in kg divided by height in meters squared. Imperial BMI equals 703 times weight in lb divided by height in inches squared. BMI Prime equals BMI divided by 25.

About the BMI Calculator

The BMI Calculator is a free online Body Mass Index checker with ideal-weight range, BMI Prime, body-fat estimate and waist-to-height ratio for adults and kids guidance.

Built for families, students and athletes in India, it supports age, gender, metric and imperial inputs and runs privately in your browser with no signup.

Related Tools

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Percentage Calculator

Methodology & feedback

Figures run locally in your browser from the values you enter (page updated 2026-10-05). Estimates are educational only — verify finance, tax and health decisions with a qualified professional (see Disclaimer). Spotted an error? Report it via contact and we correct with a new update date.

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