BMI Calculator
Calculate your Body Mass Index with ideal weight range — uses Asian BMI cut-offs recommended by WHO
| Underweight | Below 18.5 |
| Normal weight | 18.5 – 22.9 |
| Overweight | 23 – 24.9 |
| Obese Class I | 25 – 29.9 |
| Obese Class II | 30 and above |
BMI categories for adults (WHO Asian cut-offs)
Underweight
Risk of nutritional deficiencies, weakened immunity, and osteoporosis. Common in young adults with high metabolism or restricted diets.
Normal
The healthy range for Asian populations. Lowest risk of Type 2 diabetes, cardiovascular disease, and metabolic syndrome. Aim to stay here.
Overweight
Note: the WHO international cut-off is 25, but for Asian populations, risk increases from 23 itself due to higher body fat at the same BMI compared to Western populations.
Obese
Significantly elevated risk of diabetes, hypertension, sleep apnea, and joint problems. Medical consultation recommended for sustained weight management.
BMI is a screening tool, not a diagnosis
BMI doesn't distinguish between muscle and fat. A muscular person with visible abs can register as "overweight" while a sedentary person with excess belly fat can be "normal" BMI. For a complete picture, measure your waist circumference (risk increases above 90cm for men, 80cm for women in Asian populations) and get a body composition test if possible. BMI works best as a population-level indicator, not an individual health verdict.
Small changes that move the needle
Losing just 5-7% of body weight reduces Type 2 diabetes risk by 58% according to the Diabetes Prevention Program study. For a 85kg person, that's only 4-6 kg. A 30-minute daily walk burns roughly 150 calories — enough to lose 0.5 kg per month without any dietary change. Combine it with reducing one sugary drink per day and you're looking at 1 kg/month of sustainable loss.
Frequently Asked Questions
What is BMI and how is it calculated?
BMI (Body Mass Index) is calculated by dividing your weight in kilograms by the square of your height in metres (kg/m²). For example, a person 170cm tall weighing 70kg has BMI = 70 ÷ (1.70²) = 24.2.
What are the BMI categories for Asian populations?
The World Health Organization (WHO) uses modified cut-offs for Asian populations: Underweight (< 18.5), Normal weight (18.5–22.9), Overweight (23–24.9), Obese Class I (25–29.9), Obese Class II (≥ 30). Asian populations carry higher cardiovascular risk at lower BMIs compared to Western populations.
Is BMI an accurate measure of health?
BMI is a useful screening tool but has limitations. It does not account for muscle mass, bone density, or fat distribution. Athletes may have high BMI due to muscle. Older adults may have normal BMI but excess fat. Use BMI alongside waist circumference and medical advice for a complete picture.
Does a high BMI affect health insurance premiums?
Yes. Most health insurers use BMI as a risk factor. BMI above 30 (obese) may lead to higher premiums or exclusions on certain conditions. Maintaining a healthy BMI (18.5–22.9 for Asian populations, 18.5–24.9 internationally) often qualifies you for lower-premium health insurance plans.
What is the ideal waist-to-height ratio?
A waist-to-height ratio below 0.5 is considered healthy. This means your waist circumference should be less than half your height. For a 170cm person, waist should be under 85cm. This metric is increasingly recommended alongside BMI because it better predicts abdominal fat and cardiovascular risk.
Key Terms
BMI
Body Mass Index — a numerical value calculated from weight and height (kg/m²) used as a screening tool for weight categories.
Asian Cut-offs
WHO recommends lower BMI thresholds for Asian populations: overweight starts at 23 (not 25) due to higher body fat percentage at the same BMI compared to Western populations.
Ideal Body Weight
The weight range that corresponds to a BMI of 18.5–22.9 for your height. This range is associated with the lowest health risk for Asian populations.
Waist Circumference
Measured at the navel level. For Asian populations, risk increases above 90cm for men and 80cm for women — a better predictor of metabolic risk than BMI alone.