Check your BMI (Body Mass Index) and understand what your weight means for your health. Use our simple, fast, and mobile-friendly BMI calculator designed for both men and women.
What is BMI?
BMI (Body Mass Index) is a number calculated from your height and weight. It helps determine whether you’re underweight, normal weight, overweight, or obese based on standard health guidelines. It’s widely used by doctors and fitness professionals to screen for weight-related health risks.
The formula is simple:
BMI = Weight (kg) / [Height (m)]²
It gives a single number that fits into a specific BMI category.
BMI Classification Chart (WHO Standard)
BMI Range | Classification |
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Less than 18.5 | Underweight |
18.5 – 24.9 | Normal Weight |
25 – 29.9 | Overweight |
30 – 34.9 | Obese Class I |
35 – 39.9 | Obese Class II |
40 and above | Obese Class III |
Note: These classifications are for adults aged 18 to 65.
How to Use This BMI Calculator
Using our calculator is simple:
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Enter your weight (in kilograms or pounds).
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Enter your height (in centimeters or feet/inches).
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Hit Calculate.
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Instantly get your BMI result and interpretation.
✅ Works on all devices
✅ No signup required
✅ Free and instant results
Why BMI Matters
Understanding your BMI can help you:
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Assess your risk of developing heart disease, type 2 diabetes, and hypertension.
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Plan a diet or fitness routine.
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Have meaningful discussions with your healthcare provider.
Limitations of BMI
BMI is a helpful screening tool, but it’s not perfect. It doesn’t:
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Differentiate between fat and muscle.
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Account for age, gender, ethnicity, or bone density.
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Apply directly to athletes, children, pregnant women, or elderly individuals.
For example: A bodybuilder might have a high BMI due to muscle mass, not fat.
For a more accurate picture of health, use additional tools:
BMI for Men vs Women
While the formula stays the same, body fat distribution differs:
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Men tend to carry more fat in the abdomen.
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Women carry more fat in the hips and thighs.
BMI doesn’t capture these differences, so it’s smart to combine it with waist circumference or body fat % for better insight.
BMI by Age
BMI ranges stay the same for adults, but aging affects body composition:
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Older adults may have more fat and less muscle at the same BMI.
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Children and teens use BMI-for-age percentiles, not the adult scale.
For children and teens, use dedicated calculators or consult a doctor.
BMI and Ethnicity
Different ethnic groups may have different risk thresholds. For example:
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Asian populations face higher health risks at lower BMIs. A BMI over 23 may already indicate risk.
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Pacific Islanders may naturally have higher muscle mass, making BMI less reliable.
Some countries (like India, Japan, or China) follow adjusted BMI cut-offs.
Health Risks of High BMI
If your BMI is over 25, here’s what you might be at risk for:
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Type 2 Diabetes
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Heart Disease
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High Blood Pressure
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Sleep Apnea
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Stroke
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Certain Cancers
Even moderate weight loss (5–10% of your body weight) can significantly reduce these risks.
Health Risks of Low BMI
A BMI below 18.5 isn’t safe either. It may suggest:
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Malnutrition
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Weakened immune system
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Osteoporosis
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Infertility
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Anemia
Low BMI may result from underlying medical issues. Always consult your doctor.
Tips for Reaching a Healthy BMI
To lower BMI:
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Cut processed foods and sugary drinks.
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Increase physical activity—aim for 150 minutes/week.
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Focus on strength training to build muscle mass.
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Monitor your calorie intake vs output.
To increase BMI:
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Add healthy fats (avocados, nuts, olive oil).
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Eat more frequent, nutrient-dense meals.
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Do resistance training to gain lean muscle.
What to Do After Checking Your BMI
Your BMI is just the starting point. Depending on your result:
✅ Normal range? Great—focus on maintenance.
⚠️ Too low or too high? It’s time to build a plan with a certified health coach or doctor.
You can also try other health tools:
BMI Alternatives
BMI doesn’t tell the whole story. Consider these:
Tool | What it Measures |
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Body Fat % | Actual fat vs lean tissue |
BMR | Daily calories burned at rest |
Waist-to-Hip | Fat distribution and abdominal risk |
WHtR | Waist-to-height ratio, good for cardio risk |
Frequently Asked Questions (FAQs)
1. What is the normal BMI range?
For adults, 18.5 to 24.9 is considered normal. It may differ based on ethnicity or age.
2. Can BMI tell me if I’m healthy?
Not entirely. It gives an estimate of weight-related risk, but not full body composition or overall health.
3. Is BMI accurate for athletes?
No. Athletes often have high muscle mass, which skews BMI readings upward.
4. How often should I check my BMI?
Every 3–6 months is reasonable unless your weight changes dramatically.
5. Can children use this BMI calculator?
No. Children should use BMI-for-age percentiles with pediatric guidance.