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BMI Calculator

Body Mass Index with WHO and Asia-Pacific cut-offs, ideal weight range, BMR/TDEE and waist-to-height ratio.

Normal

BMI

22.9

Normal

Ideal weight

56.7–76.3 kg

BMI Prime

0.91

BMR

1,659 kcal

TDEE

2,571 kcal

Healthy weight goal (BMI 22)

67.4 kg

Lose 2.6 kg · ~550 kcal/day

BMI 22.9, Normal

Health disclaimer: This result is for general informational purposes only and is not medical advice. Individual health needs vary — consult a qualified healthcare professional before making health, diet, or medical decisions.

📐 About This Calculator

Body Mass Index estimates whether your weight is healthy for your height. It is a quick screening tool, not a diagnosis — it does not distinguish muscle from fat.

METRIC: BMI = Weight(kg) ÷ Height(m)² IMPERIAL: BMI = Weight(lb) × 703 ÷ Height(in)² IDEAL WEIGHT: Min = 18.5 × Height(m)² Max = 24.9 × Height(m)² BMI PRIME = BMI ÷ 25 PONDERAL INDEX = Weight(kg) ÷ Height(m)³

Variable Definitions:

  • BMI Prime = BMI ÷ 25 — 1.0 is the upper normal limit
  • Ponderal Index = weight ÷ height³ — more stable for very tall/short people

✅ Best used for:

  • A first screen of weight-related health risk
  • Tracking change over time
  • Setting a healthy weight goal

⚠️ Limitations:

  • Does not separate muscle mass from fat mass
  • Less accurate for pregnant people, children and the elderly
  • Asian populations use a lower threshold (23 = overweight)

📖 How BMI is Calculated

What is BMI and why it matters

BMI, devised by Adolphe Quetelet (1832), turns weight and height into a single number that the WHO and clinicians use as a screening tool for weight-related risk.

Metric vs imperial

Metric divides weight in kg by height in metres squared. Imperial uses (lb × 703) ÷ inches². This calculator converts automatically whichever units you enter.

BMI Prime and Ponderal Index

BMI Prime is your BMI ÷ 25; 1.0 sits exactly at the upper healthy limit. The Ponderal Index divides weight by height cubed and is slightly more reliable for very tall or short people.

A note for Asian populations

The WHO Asia-Pacific thresholds are lower: overweight starts at 23 and obesity at 27.5. Toggle to Asia-Pacific if that scale fits you better.

Limitations

BMI only compares weight to height. A muscular athlete can read as "obese" while being healthy, so treat BMI as a starting point — your doctor makes the final call.

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