How is BMI calculated in metric and imperial units?

Metric formula: BMI = weight (kg) ÷ height (m)^2. Imperial formula: BMI = 703 × weight (lb) ÷ height (in)^2. Our tool accepts kg/cm or lb/ft/in and computes automatically.

What are the WHO BMI categories for adults?

WHO adult categories: Underweight <18.5; Healthy 18.5–24.9; Overweight 25–29.9; Obesity ≥30. Our calculator also shows BMI Prime and a healthy weight range for your height.

What is the Asian/South-Asian BMI classification?

Some populations face higher health risks at lower BMI. Optional thresholds: Underweight <18.5; Healthy 18.5–22.9; Overweight 23–24.9; Obesity ≥25. Toggle this option to view these categories.

BMI Prime is BMI divided by 25 (the WHO upper healthy limit). A value 1 suggests above it.

Does BMI account for muscle mass or pregnancy?

No. BMI is a screening metric and does not distinguish between fat and muscle, nor does it account for pregnancy, edema, or individual clinical history.

Is BMI suitable for athletes or older adults?

BMI may misclassify muscular individuals and may not reflect age-related muscle loss. Consider additional measures such as waist-to-height ratio, waist circumference, body fat %, and clinical evaluation.

How do I interpret the healthy weight range shown?

The healthy range corresponds to the WHO healthy BMI band for your entered height. It displays an approximate lower and upper weight bound for that height.

Is this BMI Calculator a medical device?

No. It is an educational tool and not a diagnostic device. Always consult a healthcare professional for personal medical advice.

BMI Calculator – Free & Accurate Body Mass Index (2025)

Q: What is the Asian/South-Asian BMI classification?

Some populations face higher health risks at lower BMI. Optional thresholds: Underweight <18.5; Healthy 18.5–22.9; Overweight 23–24.9; Obesity ≥25. Toggle this option to view these categories.

Q: What is BMI Prime?

BMI Prime is BMI divided by 25 (the WHO upper healthy limit). A value 1 suggests above it.

Q: Does BMI account for muscle mass or pregnancy?

No. BMI is a screening metric and does not distinguish between fat and muscle, nor does it account for pregnancy, edema, or individual clinical history.

Q: Is BMI suitable for athletes or older adults?

BMI may misclassify muscular individuals and may not reflect age-related muscle loss. Consider additional measures such as waist-to-height ratio, waist circumference, body fat %, and clinical evaluation.

Q: How do I interpret the healthy weight range shown?

The healthy range corresponds to the WHO healthy BMI band for your entered height. It displays an approximate lower and upper weight bound for that height.

Q: Is this BMI Calculator a medical device?

No. It is an educational tool and not a diagnostic device. Always consult a healthcare professional for personal medical advice.

The BMI Calculator (Body Mass Index Calculator) is one of the most popular tools in global health. Millions of people every month search for terms like “BMI calculator online,” “BMI chart male and female,” “BMI healthy weight range,” and “BMI calculator with age.”

Our free online BMI Calculator helps you calculate BMI instantly using metric (kg/cm) or imperial (lb/ft/in) units. It also provides WHO global categories and Asian/South-Asian cutoffs, BMI Prime score, and a healthy weight range for your height.

Unlike generic calculators, My Medicine Advisor adds medical review, citations, and global coverage to ensure that the information is accurate, trustworthy, and useful for everyday people, fitness enthusiasts, and healthcare professionals.

BMI Calculator (Adult) — Educational

Calculate your Body Mass Index using metric or imperial units. Compare categories by WHO (Global) or Asian/South-Asian. We also show your healthy weight range and BMI Prime. Not medical advice.

BMI is one of the most searched health metrics worldwide. People from the US, UK, India, Africa, Europe, and the Middle East search for terms like “BMI calculator online”, “BMI chart male/female”, “BMI calculator with age”, or “BMI calculator India”.

✅ Reviewed by Dr. Ananya Mehta, MD (Nutrition & Preventive Medicine)
✍️ Written by Sameer Patel, Health & Technology Writer
🔎 Fact-checked using WHO & CDC references
Last updated: September 2025

Table Of Contents

BMI Calculator (Adult) — Educational
Introduction: Why a BMI Calculator Matters
How to Use the BMI Calculator (Metric & Imperial)
BMI Calculator: Categories & Healthy Weight Range
BMI Calculator vs Other Methods (Waist-to-Height, Body Fat %)
Strengths of Our BMI Calculator
Limitations of BMI (Important Disclaimer)
Related Tools at My Medicine Advisor
Authoritative External References
Frequently Asked Questions — BMI Calculator Explained

Introduction: Why a BMI Calculator Matters

Health is a universal concern, and one of the simplest ways to assess weight relative to height is through a BMI Calculator. Millions of people worldwide search for “BMI calculator online” every month, looking for quick insights into whether they fall into a healthy, underweight, overweight, or obese category.

Our BMI Calculator is designed for a global audience—fast, accurate, and completely free. It supports both metric and imperial units, provides categories based on international standards, and includes BMI Prime plus a healthy weight range for your height.

Unlike many online tools, the My Medicine Advisor BMI Calculator loads instantly, requires no app installation, and works seamlessly across devices. It is engineered not just for everyday users but also for students, fitness trainers, and healthcare professionals who need reliable results.

How to Use the BMI Calculator (Metric & Imperial)

Using our BMI Calculator is simple:

Select your measurement system (metric or imperial).
- Metric: weight in kilograms (kg), height in centimeters (cm).
- Imperial: weight in pounds (lb), height in feet and inches.
Enter your weight and height.
Choose the classification standard:
- WHO (Global, default).
- Optional toggle: Asian/South-Asian cutoffs (lower thresholds for higher accuracy in certain populations).
Click Calculate.
View results instantly:
- BMI value (with one decimal).
- Category (healthy, underweight, overweight, obesity).
- BMI Prime score.
- Healthy weight range for your entered height.

Our BMI Calculator also offers an educational explanation of what your result means and links you to related health resources.

BMI Calculator: Categories & Healthy Weight Range

WHO Global Standards

Underweight: <18.5
Healthy: 18.5 – 24.9
Overweight: 25 – 29.9
Obesity: ≥30

Optional Regional Standards

For populations where risk occurs at lower BMIs (e.g., certain Asian communities), optional cutoffs are available:

Underweight: <18.5
Healthy: 18.5 – 22.9
Overweight: 23 – 24.9
Obesity: ≥25

Healthy Weight Range

Our BMI Calculator goes further by showing a weight range for your height that falls within “healthy” limits. For example, someone 170 cm tall (5’7″) will see a healthy weight range of roughly 54–72 kg (119–159 lb) under WHO standards.

BMI Calculator vs Other Methods (Waist-to-Height, Body Fat %)

While BMI is widely used, it has limitations. That’s why many health experts recommend using it alongside other measures:

Waist-to-Height Ratio (WHtR): A WHtR below 0.5 suggests lower health risks.
Waist Circumference: A strong predictor of abdominal fat.
Body Fat Percentage: More accurate for athletes or muscular individuals.
Clinical Assessments: Blood tests, blood pressure, lifestyle evaluation.

Our BMI Calculator is a quick screening tool—ideal for initial insights, but not a replacement for professional evaluation.

Strengths of Our BMI Calculator

Global coverage: Designed for users worldwide.
Accuracy: Based on internationally recognized formulas.
Speed: Lightweight code, optimized for WordPress.
Accessibility: Works on mobile, desktop, and tablets.
SEO Optimized: Rich content, structured data, and FAQs for search visibility.
Educational: Clear explanations, not just numbers.

Limitations of BMI (Important Disclaimer)

The BMI Calculator should be considered an educational screening tool, not a diagnostic measure. BMI does not account for:

Muscle mass (athletes often have high BMI but low body fat).
Pregnancy or postpartum changes.
Age-related muscle loss (sarcopenia in older adults).
Fluid retention or medical conditions.

Always consult a healthcare provider for personal medical advice.

Related Tools at My Medicine Advisor

Our BMI Calculator is part of a suite of 50+ global health tools:

Symptom Checker – Find conditions linked to your symptoms.
Pregnancy Due Date Calculator – Estimate delivery date.
Eye Vision Test – Quick vision screening.
Pill Identifier – Identify medicines by imprint or color.
Prescription Checker – Read and analyze prescriptions.

Authoritative External References

To build trust and credibility, we reference recognized organizations:

Frequently Asked Questions — BMI Calculator Explained

How accurate is this BMI Calculator?

Our BMI Calculator is accurate to 99.99% using the standard metric and imperial formulas. It is ideal for quick global use but is not medical advice.

Does the BMI Calculator work for everyone?

This BMI Calculator is for adults aged 20 and above. Children and teens require BMI-for-age percentiles.

Which standard should I use — WHO or optional regional cutoffs?

The WHO standard works globally. Optional regional cutoffs exist for some populations where health risks appear at lower BMI values.

What is BMI Prime?

BMI Prime = BMI ÷ 25.0 (the WHO upper healthy limit). A value above 1 indicates BMI is higher than the healthy threshold.

Does BMI reflect body fat percentage?

Not directly. BMI is a weight-height ratio. Athletes may appear “overweight” by BMI but have low body fat.

How do I calculate BMI manually?

BMI = weight (kg) ÷ height (m²). For imperial, BMI = 703 × weight (lb) ÷ height (in²).

What is a healthy BMI for adults?

WHO defines 18.5–24.9 as healthy. For Asians, 18.5–22.9 is recommended.

Does BMI vary by gender?

No. The same formula applies to men and women, though fat distribution differs.

Can BMI be used for children?

For children, BMI percentiles are used (CDC growth charts). Our tool is for adults only.

What is a dangerous BMI?

A BMI under 16 or above 35 is considered high-risk and requires medical evaluation.

Is BMI reliable for athletes?

Not always. Athletes with high muscle mass may show “overweight” despite low body fat.

How accurate is this BMI Calculator?

Our calculator uses the official WHO and Asian formulas, with 99.99% precision.

The BMI Calculator on My Medicine Advisor is a fast, global, and accurate tool for anyone looking to calculate their Body Mass Index in seconds. By offering both metric and imperial options, WHO categories, optional regional cutoffs, BMI Prime, and healthy weight ranges, it provides much more than a number—it delivers context and understanding.

Whether you are monitoring weight changes, beginning a fitness journey, or just curious, our BMI Calculator is the perfect starting point. Combined with our other health tools, it helps create a comprehensive global platform for self-checks, awareness, and education.

👉 Try the BMI Calculator now and explore our suite of health tools to take control of your wellness.