⚖️ BMI Calculator
Calculate your Body Mass Index instantly. Free, fast, and accurate. Supports metric and imperial units.
Your Result
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| BMI Range | Category | Health Risk |
|---|
| Below 18.5 | Underweight | Moderate (malnutrition risk) |
| 18.5 – 24.9 | Normal Weight | Low (healthy range) |
| 25.0 – 29.9 | Overweight | Moderate |
| 30.0 – 34.9 | Obese Class I | High |
| 35.0 – 39.9 | Obese Class II | Very High |
| 40.0 and above | Obese Class III | Extremely High |
What is BMI?
BMI (Body Mass Index) is a widely used measurement that estimates body fat based on height and weight. It was developed by Adolphe Quetelet in the 19th century and is used by health professionals worldwide as a quick screening tool.
BMI Formula
Metric: BMI = Weight (kg) ÷ Height² (m)
Imperial: BMI = (Weight (lbs) × 703) ÷ Height² (inches)
Limitations of BMI
BMI does not directly measure body fat and may be inaccurate for athletes (high muscle mass), elderly individuals, or pregnant women. Always consult a healthcare provider for a comprehensive health assessment.
Frequently Asked Questions
What is a normal BMI range?
A normal BMI range is 18.5 to 24.9. Below 18.5 is underweight, 25–29.9 is overweight, and 30 and above is obese. Use our BMI Calculator above to check your score.
How to calculate BMI in kg and cm?
BMI = Weight (kg) ÷ Height² (m). First convert height from cm to m (e.g. 170 cm = 1.70 m). Then divide weight by height squared. Example: 70 kg ÷ (1.70 × 1.70) = 24.2 BMI.
Is BMI accurate for Indians?
Studies suggest that Indians and South Asians have a higher risk of metabolic disease at lower BMI values. Some health organizations recommend using lower BMI cutoffs (23 for overweight, 27.5 for obese) for Indian populations.
What is the ideal weight for my height?
Ideal weight depends on your height. Using BMI: Ideal weight = 18.5 to 24.9 × Height² (m). For a 5'6" (168 cm) person: ideal weight range ≈ 52 kg to 70 kg.
BMI Categories and What They Mean
According to the World Health Organization, adult BMI is grouped into the following categories:
- Below 18.5: Underweight
- 18.5 to 24.9: Normal weight
- 25 to 29.9: Overweight
- 30 and above: Obese
Some health bodies in Asia, including guidelines used for Indian adults, suggest lower cut-offs (for example, overweight from 23) because the risk of diabetes and heart disease can rise at a lower BMI in South Asian populations. Treat these ranges as a screening guide rather than a diagnosis.
Worked Example
Suppose a person weighs 70 kg and is 1.75 m tall. Height squared is 1.75 × 1.75 = 3.0625. BMI = 70 ÷ 3.0625 = 22.9, which falls in the normal weight range. If the same person weighed 85 kg, BMI would be 85 ÷ 3.0625 = 27.8, which is in the overweight range.
Who Should Be Careful With BMI?
BMI does not separate muscle from fat, so athletes and people with a lot of muscle can show a high BMI without excess body fat. It is also not designed for children and teenagers (who use age-based percentile charts), pregnant women, or older adults who may have lost muscle mass. Waist circumference, body fat percentage and blood tests give a more complete picture.
Tips to Maintain a Healthy BMI
- Eat a balanced diet with vegetables, fruit, protein and whole grains
- Aim for at least 150 minutes of moderate activity per week
- Sleep 7 to 9 hours a night and manage stress
- Drink enough water and limit sugary drinks and processed snacks
- Talk to a doctor or dietitian before starting any major diet or exercise plan
Why BMI Matters — Know More
BMI is a starting point for understanding your health. For a complete picture, track your weight regularly and pair it with a healthy lifestyle.
If you are planning a diet or fitness loan, our EMI Loan Calculator helps plan finances.
Use our Age Calculator to understand BMI norms for your age group.
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BMI kaise nikale? (Hinglish me)
BMI ka formula hai: weight (kg) ÷ height (meter) ka square. Jaise 70 kg weight aur 170 cm (1.70 m) height par BMI = 70 ÷ (1.70 × 1.70) = 24.2, jo normal range (18.5 se 24.9) me aata hai.
BMI sirf ek screening measure hai, body fat ka seedha maap nahi. Kuch health guidelines Bharat ke liye lower cut-off (overweight ke liye 23) suggest karti hain, isliye apne doctor se salah zaroor lo.