Hamwi + HPB Asian Standard
Ideal Weight Calculator
Find your ideal weight using Singapore HPB healthy BMI range and the Hamwi formula. Compare Asian (BMI 18.5–22.9) vs WHO (18.5–24.9) healthy weight ranges for your height.
Why Singapore Uses Different Healthy Weight Ranges
The World Health Organisation defines overweight as BMI ≥ 25.0. Singapore's Health Promotion Board sets a lower threshold of BMI ≥ 23.0, with obesity beginning at BMI 27.5 rather than 30.0. This isn't arbitrary — it reflects robust evidence specific to Asian physiology.
Multiple studies across Chinese, Malay, and Indian populations (all present in Singapore) show that Asians accumulate significantly more visceral (abdominal) fat at the same BMI compared to people of European descent. Visceral fat is metabolically active and strongly associated with type 2 diabetes, cardiovascular disease, and metabolic syndrome — all of which are priority health concerns in Singapore.
For practical purposes, this means your healthy weight target should be based on HPB standards, not the WHO figures printed on most international charts. This calculator defaults to the HPB range.
Asian HPB vs WHO BMI Standards
| Category | Singapore HPB (Asian) | WHO (Global) |
|---|---|---|
| Underweight | < 18.5 | < 18.5 |
| Healthy | 18.5 – 22.9 | 18.5 – 24.9 |
| Overweight | 23.0 – 27.4 | 25.0 – 29.9 |
| Obese Class I | 27.5 – 32.4 | 30.0 – 34.9 |
| Obese Class II | ≥ 32.5 | ≥ 35.0 |
HPB Healthy Weight Range by Height
Based on Singapore HPB healthy BMI range of 18.5–22.9. Ranges are the same for men and women at the same height — body composition goals may differ, but the clinical weight range does not.
| Height | Women — HPB Range | Men — HPB Range |
|---|---|---|
| 155 cm | 44.4 – 55.0 kg | 44.4 – 55.0 kg |
| 158 cm | 46.2 – 57.2 kg | 46.2 – 57.2 kg |
| 160 cm | 47.4 – 58.6 kg | 47.4 – 58.6 kg |
| 162 cm | 48.6 – 60.1 kg | 48.6 – 60.1 kg |
| 165 cm | 50.3 – 62.4 kg | 50.3 – 62.4 kg |
| 168 cm | 52.2 – 64.7 kg | 52.2 – 64.7 kg |
| 170 cm | 53.5 – 66.2 kg | 53.5 – 66.2 kg |
| 172 cm | 54.7 – 67.8 kg | 54.7 – 67.8 kg |
| 175 cm | 56.7 – 70.2 kg | 56.7 – 70.2 kg |
These ranges are calculated using BMI = weight (kg) ÷ height (m)². For individualised targets, use the calculator above which also applies the Hamwi formula for a single midpoint ideal weight value.
The Hamwi Formula Explained
Male
48.0 kg + 2.7 kg for each inch over 5 feet (152.4 cm)Female
45.5 kg + 2.2 kg for each inch over 5 feet (152.4 cm)The Hamwi formula was originally developed for clinical dietetics practice and gives a single midpoint "ideal" weight value. This calculator presents it alongside the HPB healthy BMI range, which is the more clinically relevant measure for Singapore residents. Use the HPB range as your primary target.
Frequently Asked Questions
What is the ideal weight for Singaporeans?
Singapore HPB defines healthy weight as a BMI between 18.5 and 22.9 — lower than the WHO's 18.5–24.9. For a 165cm Singaporean woman, the HPB healthy weight range is 50.3–62.4 kg. Use this calculator to find your specific range by height.
What formula is used for ideal weight?
This calculator uses two methods: (1) The HPB healthy BMI range (18.5–22.9), which gives the most clinically relevant range for Singapore. (2) The Hamwi formula — 48 kg + 2.7 kg per inch over 5ft for men; 45.5 kg + 2.2 kg per inch over 5ft for women.
Why is Singapore's healthy BMI range different from WHO?
Research shows Asians accumulate more visceral fat and face higher metabolic risk at lower BMI values than people of European descent. Singapore HPB therefore uses an overweight threshold of BMI 23.0 (not WHO's 25.0) and obese at 27.5 (not 30.0).
How can I reach my ideal weight safely?
Use the calorie deficit calculator to create a sustainable 500 kcal daily deficit for 0.5 kg/week weight loss. Combine with strength training to preserve muscle mass. Avoid crash diets — they reduce BMR and increase long-term weight regain risk.