🌍 WHO Global 🌏 Asia-Pacific 🇯🇵 Japan JASSO 🇨🇳 China WGOC 🇬🇧 NHS UK

BMI Calculator

Body Mass Index is calculated the same way everywhere — but the thresholds that define "healthy" differ by country. Enter your measurements to see your BMI under four international standards at once.

Quick Answer

Use this calculator if you want the same BMI arithmetic scored under WHO, Japan (JASSO), Asia-Pacific and China (WGOC) at once. Skip it if you are under 18, pregnant, or a high-muscle athlete — BMI is a population screen, not a diagnosis. WHO healthy BMI: 18.5–24.9. Japan classes BMI ≥25 as obese (WHO’s “overweight”). Asia-Pacific overweight starts at 23. A BMI of 26 is overweight (WHO), obese grade 1 (Japan) and overweight, at risk (Asia-Pacific, where obesity starts at 27.5).

At a glance

WHO healthy

18.5–24.9

US, Europe, Australia default

Japan obese

BMI ≥ 25

JASSO — WHO still calls this overweight

Asia-Pacific overweight

BMI ≥ 23

WHO 2004 Asian action point; NICE uses it for some groups

China overweight

BMI ≥ 24

WGOC; obese at 28

22.9
Your BMI

WHO scale

1518.5253040
Healthy weight (WHO)
56.7 kg – 76.3 kg
BMI 18.5–24.9 for this height
Asia-Pacific normal
56.7 kg – 70.1 kg
Upper cut-off BMI 22.9
BMI Prime
0.92
BMI ÷ 25. 1.0 = WHO overweight line
🌍WHO
Normal weight
US, Europe, Australia
🇨🇳China
Normal weight
WGOC 2004 standard
🌏Asia-Pacific
Normal weight
Singapore, Hong Kong, Taiwan
🇯🇵Japan
Normal weight
Japan, South Korea

  1. 1
    Convert height to metres
    175 cm ÷ 100
    1.75 m
  2. 2
    Apply BMI formula: weight ÷ height²
    70 ÷ (1.75)² = 70 ÷ 3.0625
    BMI = 22.9
  3. 3
    Classify against international standards
    WHO: <18.5 under, 18.5–24.9 normal, 25–29.9 over, ≥30 obese
    WHO: Normal weight · Asia-Pacific: Normal weight
  4. 4
    BMI Prime (BMI ÷ 25)
    22.9 ÷ 25
    0.92

Run a site? Embed this BMI calculator on your own pages — free, four standards, no signup.

How is BMI calculated?

BMI is weight in kilograms divided by height in metres squared. In imperial units it is pounds times 703, divided by height in inches squared. Every country on this page uses that same arithmetic — the only thing that changes is the labelled category, which is why a BMI of 26 can be overweight in the US and obese in Japan.

BMI = weight (kg) ÷ height² (m²)

What BMI is obese in Japan versus WHO?

Japan’s JASSO guideline labels BMI 25 and above as obese. WHO labels 25–29.9 as overweight and 30+ as obese. Asia-Pacific action points (WHO expert consultation, 2004) flag increased risk from 23 and high risk from 27.5. China (WGOC) uses overweight at 24 and obesity at 28. Check the table — the formula did not change; the public-health cut-off did. Sources: WHO 2000, WPRO/IASO 2000, JASSO 2011, WGOC 2004, reviewed June 2026.

Category 🌍 WHO / Global 🌏 Asia-Pacific 🇯🇵 Japan 🇨🇳 China WGOC
Underweight < 18.5< 18.5< 18.5< 18.5
Normal weight 18.5 – 24.918.5 – 22.918.5 – 24.918.5 – 23.9
Overweight 25.0 – 29.923.0 – 27.4≥ 25 = Obese24.0 – 27.9
Obese / At risk ≥ 30.0≥ 27.5— (all ≥25 = obese)≥ 28.0

Sources: WHO 2000; WHO expert consultation on Asian populations, Lancet 2004; JASSO 2011; WGOC 2004; NICE NG246.

Why does Japan use a different BMI standard?

JASSO set obesity at BMI 25 because East Asian populations tend to carry more body fat, and to develop type 2 diabetes and metabolic syndrome, at a lower BMI than European-descent populations. The lower cut-off is a clinical-risk choice, not a translation quirk. It is also why Japan’s official obesity rate looks low: the same body can be “overweight” in New York and “obese grade 1” in Tokyo.

🧬
Body composition

At the same BMI, East Asian people typically have a higher percentage of body fat than people of European descent.

📉
Health risk evidence

Type 2 diabetes, hypertension, and metabolic syndrome appear at lower BMI values in East Asian populations — consistent across multiple large studies.

🏥
Public health policy

Japan's stricter threshold triggers earlier preventative care. It contributes to Japan having one of the world's lowest obesity rates by their own measure.

Who should skip this BMI calculator?

Skip it if you are a child or teenager (ages 2–19 need percentile charts, not adult cut-offs), if you are pregnant, or if you have high muscle mass — BMI cannot tell fat from muscle. Use it as a first screen, then add waist circumference and a clinician. The UK NHS still uses WHO cut-offs for most adults, but NICE sets lower thresholds (23 and 27.5) for people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background.

Doesn't distinguish muscle from fat

A muscular athlete may have BMI 28 without excess body fat. Bodybuilders routinely score "obese" by BMI.

Doesn't measure fat distribution

Central (abdominal) fat is more metabolically dangerous than fat elsewhere. BMI doesn't capture this — waist circumference does.

Age differences

Older adults often have "normal" BMI but higher fat percentage due to muscle loss. Younger adults may be healthy at the same BMI.

Sex differences

Women naturally carry more body fat than men at the same BMI. Sex-specific BMI interpretations exist but aren't widely used clinically.

Key takeaways

  • WHO healthy BMI for most adults is 18.5–24.9. Japan (JASSO) classes BMI ≥25 as obese — the same body WHO still calls overweight.
  • Asia-Pacific overweight starts at 23; China (WGOC) at 24; obesity at 27.5 (Asia-Pacific) and 28 (China).
  • The formula never changes. Only the labelled category changes. That is why a BMI of 26 can mean opposite advice in New York and Tokyo.
  • BMI Prime is BMI ÷ 25 (1.0 = WHO overweight line). The result also shows the healthy weight range for your height under WHO and Asia-Pacific cut-offs.
  • Skip adult BMI cut-offs for children, pregnancy, and high-muscle athletes. Pair with waist circumference and a clinician.

FAQ

BMI questions, answered straight

What is a healthy BMI according to WHO? ▾
According to the World Health Organization (WHO), a BMI between 18.5 and 24.9 is considered normal weight. Under 18.5 is underweight. 25–29.9 is overweight. 30 or above is obese. These thresholds apply in the United States, Europe, Australia, and most of the world.
What BMI is considered obese in Japan? ▾
In Japan, a BMI of 25 or above is classified as obese (肥満, Himan) by the Japan Society for the Study of Obesity (JASSO). This is significantly lower than the WHO obesity threshold of 30. A BMI of 26 is “overweight” by WHO but “obese grade 1” in Japan.
Why are BMI standards different in Asian countries? ▾
Research shows that at the same BMI, people of East and South Asian descent tend to have a higher percentage of body fat and develop metabolic conditions at lower BMI values than people of European descent. A 2004 WHO expert consultation on Asian populations set public-health action points at BMI 23 (increased risk) and 27.5 (high risk), lower than the global WHO cut-offs of 25 and 30. This calculator uses those 23 and 27.5 points for its Asia-Pacific result.
How is BMI calculated? ▾
BMI = weight (kg) ÷ height² (m²). In imperial units: BMI = (weight in lbs × 703) ÷ height in inches². The formula is the same worldwide — only the category thresholds differ between countries.
What is the BMI overweight threshold in China? ▾
China uses the WGOC (Working Group on Obesity in China) standard: BMI ≥24 is overweight and BMI ≥28 is obese. This is stricter than WHO (overweight ≥25, obese ≥30) but less strict than Japan (obese ≥25).
Do UK doctors use a different BMI standard? ▾
The UK NHS uses WHO BMI classifications (overweight ≥25, obese ≥30) for most patients. However, NICE guidance tells clinicians to use lower thresholds — overweight from 23 and obesity from 27.5 — for people of South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background.
Is BMI calculated differently for children? ▾
Yes. For children and teens (ages 2–19), BMI is interpreted using age- and sex-specific growth charts, not fixed cut-off numbers. Adult BMI thresholds (18.5, 25, 30) do not apply to children.
What is a healthy BMI for a 5'9 adult? ▾
At 5'9" (175.3 cm), a healthy BMI of 18.5–24.9 means a weight of approximately 125–169 lbs (57–77 kg) by WHO standards. Under Asia-Pacific guidelines, the normal range is 18.5–22.9, which is approximately 125–155 lbs (57–70 kg) at that height.
Who should skip this BMI calculator? ▾
Skip it if you are under 18, pregnant, or a high-muscle athlete. BMI cannot tell fat from muscle or where fat sits. Use it as a first screen, then add waist circumference and a clinician.
What BMI is considered healthy in South Korea? ▾
South Korea’s obesity society (KSSO) uses normal 18.5–22.9, pre-obese 23.0–24.9 and obese ≥25. That obesity line is stricter than both WHO (30) and the Asia-Pacific action point of 27.5 used in this calculator, so a Korean BMI of 25–27.4 shows here as “overweight (at risk)” rather than obese.
What is BMI Prime? ▾
BMI Prime is your BMI divided by 25, the WHO upper limit of the “normal” range. A Prime of 1.0 is BMI 25. Below 1.0 sits inside the WHO healthy band for most adults; above 1.0 is overweight or obese on that scale. Asia-Pacific and Japanese cut-offs still apply to the raw BMI, not to Prime.

BMI calculator by country

🇯🇵 日本語 🇩🇪 Deutsch 🇫🇷 Français 🇰🇷 한국어 🇪🇸 Español 🇧🇷 Português 🇮🇹 Italiano 🇦🇪 عربي (UAE) 🇮🇳 भारत 🇨🇳 中国 🇮🇩 Indonesia 🇷🇺 Россия 🇹🇷 Türkiye 🇹🇭 ประเทศไทย 🇻🇳 Việt Nam 🇵🇱 Polska 🇳🇱 Nederland 🇲🇽 México 🇲🇾 Malaysia 🇵🇭 Pilipinas 🇵🇰 پاکستان 🇧🇩 বাংলাদেশ 🇵🇹 Portugal 🇹🇼 台灣 🇳🇬 Nigeria 🇸🇬 Singapore 🌍 الدول العربية 🇬🇷 Ελλάδα +54 more →

Which country BMI pages are worth opening?

We keep translated and country-specific BMI pages that add local authority guidance. Thin English name-swap URLs redirect here so they cannot dilute the canonical tool.

🇯🇵 Japan 🇩🇪 Germany 🇫🇷 France 🇰🇷 South Korea 🇪🇸 Spain 🇧🇷 Brazil 🇮🇹 Italy 🇦🇪 UAE 🇮🇳 भारत 🇨🇳 中国 🇮🇩 Indonesia 🇷🇺 Россия 🇹🇷 Türkiye 🇹🇭 ประเทศไทย 🇻🇳 Việt Nam 🇵🇱 Polska 🇳🇱 Nederland 🇲🇽 México 🇲🇾 Malaysia 🇵🇭 Pilipinas 🇵🇰 پاکستان 🇧🇩 বাংলাদেশ 🇵🇹 Portugal 🇹🇼 台灣 🇳🇬 Nigeria 🇸🇬 Singapore 🌍 الدول العربية 🇬🇷 Ελλάδα 🇷🇴 România 🇸🇪 Sverige 🇳🇴 Norge 🇩🇰 Danmark 🇫🇮 Suomi 🇿🇦 South Africa 🇦🇺 Australia 🇬🇧 United Kingdom 🇨🇦 Canada 🇺🇸 United States 🇨🇴 Colombia 🇨🇱 Chile 🇵🇪 Perú 🇻🇪 Venezuela 🇨🇿 Česko 🇭🇺 Magyarország 🇧🇬 България 🇺🇦 Україна 🇭🇷 Hrvatska 🇸🇦 السعودية 🇪🇬 مصر 🇯🇴 الأردن 🇮🇱 ישראל 🇮🇷 ایران 🇱🇰 Sri Lanka 🇳🇵 नेपाल

Sources & Methodology

BMI is weight (kg) divided by height (m) squared. We use the WHO international cut-offs as the default and surface country-specific thresholds (e.g. the lower overweight cut-offs used across much of Asia) where national bodies differ.

Standards and figures reviewed 2026.

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Cite this page APA · MLA · BibTeX

APA

WorldCalculators.org. (2026, September 25). BMI Calculator (kg or lb): WHO & Asian BMI Ranges. https://worldcalculators.org/calculators/bmi/

MLA

“BMI Calculator (kg or lb): WHO & Asian BMI Ranges.” WorldCalculators.org, 25 Sept. 2026, worldcalculators.org/calculators/bmi/.

BibTeX

@misc{worldcalculators2026calculatorsbmi,
  title        = {BMI Calculator (kg or lb): WHO & Asian BMI Ranges},
  author       = {{WorldCalculators.org}},
  year         = {2026},
  howpublished = {\url{https://worldcalculators.org/calculators/bmi/}}
}

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