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BMI, BMR and TDEE Calculator — Asian Thresholds
Your BMI on the Asia-Pacific thresholds, where overweight starts at 23 not 25, plus the healthy weight range in kg for your height, BMR and TDEE. Free.
Asian BMI thresholds and the weight range at this height
| Category | BMI | Weight at this height (kg) |
|---|---|---|
| Underweight | 0 – 18.5 | 0.0 – 53.5 |
| Normal weight | 18.5 – 22.9 | 53.5 – 66.2 |
| Overweight | 23 – 24.9 | 66.5 – 72.0 |
| Obese class 1 | 25 – 29.9 | 72.3 – 86.4 |
| Obese class 2 | 30 and above | 86.7 and above |
Ask about this page
The AI assistant answers only questions about the calculator on this page.
BMI is a rough measure of whether your weight is proportionate to your height. The point that matters most on this page, and that catches out many people who move to Asia, is that the BMI thresholds used across Asia are stricter than the international ones published by the WHO. Research found that people of Asian descent begin to face raised risk of type 2 diabetes and heart disease at a lower BMI than Western populations, so the regional thresholds were set lower.
This calculator uses the Asia-Pacific thresholds and also works out your BMR and TDEE, which are the numbers you need if you are planning what to eat.
How it works
Calculating BMI. Divide weight in kilograms by height in metres squared. Someone weighing 65 kg at 170 cm gets 65 ÷ 1.70², which is about 22.5 — within the normal range.
How the Asian thresholds differ. The international WHO thresholds put overweight at 25 and obesity at 30. The Asia-Pacific thresholds put overweight at 23 and obesity at 25. Someone with a BMI of 24 is therefore classed as normal weight internationally but overweight regionally. For people of Asian descent, the lower thresholds track health risk more accurately.
If you are a Western resident in Thailand, this is worth understanding rather than simply applying: the stricter thresholds were derived from Asian populations, so the international figures may remain the more relevant reference for you. The table below shows both the category and the weight range it corresponds to at your height, so you can judge either way.
What BMR means. Basal metabolic rate is the energy your body uses simply to stay alive, doing nothing at all — breathing, circulating blood, running your organs. This calculator uses the Mifflin-St Jeor equation, which research has found to be the most accurate for the general population.
What TDEE means. Total daily energy expenditure is what your body actually uses across a whole day, calculated as BMR multiplied by an activity factor. It is your break-even point: eat at TDEE and your weight holds steady, eat below it and you lose, eat above it and you gain. Safe weight loss generally means eating 300 to 500 calories a day below TDEE, which works out at roughly 0.25 to 0.5 kg a week.
The limits of BMI. BMI cannot distinguish muscle from fat. Athletes and regular weight trainers often have a high BMI with very low body fat. Conversely, an older person with little muscle can have a normal BMI while carrying a lot of fat. BMI also says nothing about where fat sits, and abdominal fat carries more risk than fat elsewhere. Waist measurement is worth using alongside it.
Frequently asked questions
Why are the Asian BMI thresholds different?
Because research found that people of Asian descent carry a higher proportion of body fat at the same BMI as Western populations, and begin to face raised risk of type 2 diabetes, high blood pressure and heart disease at a lower BMI. The WHO Western Pacific region therefore set stricter thresholds, putting overweight at 23 rather than 25.
Should I use the Asian thresholds if I am not Asian?
The Asia-Pacific thresholds were derived from Asian populations, so for a person of European, African or other descent the international WHO thresholds — overweight at 25, obesity at 30 — are generally the more applicable reference, regardless of living in Thailand. This page shows the Asian categories, and the table gives the weight range for each so you can read it against whichever set applies to you. If it matters for a health decision, ask a doctor rather than relying on either table.
My BMI is high but it is muscle. Am I overweight?
No, and this is the most significant limitation of BMI. The formula uses only weight and height, with no way to tell whether that weight is muscle or fat. Athletes and regular weight trainers frequently exceed 25 with very low body fat. If that describes you, body fat percentage or waist measurement is a far better guide.
How many calories should I eat to lose weight?
Generally 300 to 500 calories a day below your TDEE, which produces a loss of about 0.25 to 0.5 kg a week — a rate that is safe and sustainable. Do not eat below your BMR for extended periods: your metabolism adapts downwards, which makes further loss harder and regain easier once you stop.
What waist measurement counts as abdominal obesity?
For Thai adults, a waist above 90 cm for men and above 80 cm for women is considered abdominal obesity, which carries high metabolic risk. Waist measurement is worth tracking alongside BMI, because fat stored in the abdomen is more harmful than subcutaneous fat elsewhere.
Sources
Rates last verified 25 Aug 2026