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BMI Calculator

What’s your Body Mass Index?

A quick screening tool that compares your weight to your height. Toggle between WHO global and Asia-Pacific thresholds.

Your details

Units
kg
30200
cm
120220

Lower thresholds — South-Asian bodies carry metabolic risk at a lower BMI.

BMI scale from underweight to obese
Your BMI is 24.2

Healthy BMI range: 18.5 – 22.9 kg/m²

  • Under Weight0–18.5
  • Normal Weight18.5–23
  • Over Weight23–25
  • Obese25+
Healthy weight for your height
53.5 kg – 66.2 kg

You're 3.8 kg above the healthy range.

You're a little above the healthy range. A modest, sustainable fat-loss phase — not a crash diet — is all this calls for. Lose it slowly and you keep the muscle.

Plan your fat loss
Underweight0–18.5
Normal18.5–23
Overweight23–25
Obese25–40+

BMI is a screening tool, not a diagnosis — it can't tell muscle from fat. Pair it with the body fat and waist-to-height calculators.

Health Insights — Overweight

You're a little above the healthy range — sustainable fat loss, not a crash diet, is what this calls for.

What this means

  • Slightly elevated risk of metabolic and joint issues
  • Highly reversible at this stage with modest changes
  • Waist and bloodwork tell more than BMI alone

Recommended actions

  • Modest daily calorie deficit (~300–500 kcal)
  • 150+ min of activity per week, including walking
  • Track weight as a 7-day average, not a daily reading

Nutrition tips

  • Protein 1.6–2.2 g/kg — it protects muscle in a deficit
  • Vegetables first on the plate; cut sugary drinks
  • Cook more meals at home; portion oil consciously

This is general health information, not medical advice. If you have any underlying conditions, talk to a healthcare provider before making major changes.

What is BMI?

Body Mass Index is a ratio of weight to height — kilograms divided by metres squared. The World Health Organization uses it as a quick screening number for whether an adult's weight sits in a healthy range. It's simple, free, and works the same way everywhere — which is exactly why it caught on. It is nota diagnosis: BMI can't tell muscle from fat and it doesn't say where fat is stored. Treat your number as a starting point, not a verdict.

How to use this calculator

  1. 1Choose metric (kg / cm) or imperial (lb / ft–in).
  2. 2Drag the sliders to your weight and height.
  3. 3Pick a reference standard — Asia-Pacific uses lower thresholds and is more appropriate for South-Asian bodies.
  4. 4Read your BMI, the band you sit in, and the healthy weight range for your height.

The BMI formula and what the bands mean

BMI uses the same formula regardless of units: weight in kilograms ÷ height in metres squared (kg/m²). For imperial units it's pounds ÷ inches² × 703. A 70 kg adult who is 1.75 m tall has a BMI of 70 ÷ (1.75 × 1.75) = 22.9.

BMICategoryWhat it means
< 18.5UnderweightMay indicate undereating or an underlying condition — worth checking with a clinician.
18.5 – 24.9Healthy weightLowest statistical risk of weight-related chronic disease for most adults.
25.0 – 29.9OverweightModestly increased risk of hypertension, type 2 diabetes and cardiovascular disease.
30.0 – 34.9Obesity class INotable risk increase; lifestyle changes typically recommended.
35.0 – 39.9Obesity class IIHigh risk; medical guidance is usually advised.
≥ 40.0Obesity class IIIVery high risk; medical intervention is commonly indicated.

The Asia-Pacific standard (used on this page by default) lowers overweight to 23 and obesity to 25, because South-Asian and East-Asian bodies develop cardiometabolic risk at a lower BMI.

When BMI gives a misleading answer

BMI was designed in the 1830s as a population statistic, not an individual diagnostic tool. It ignores body composition, so three groups routinely get a misleading reading:

  • Muscular athletes — a rugby player or competitive lifter can read overweight or obese on BMI while carrying 10% body fat. The weight is muscle, not adipose tissue.
  • Older adults — BMI can under-estimate body fat as lean muscle declines with age. A “normal” BMI at 70 may hide sarcopenic obesity.
  • South-Asian and East-Asian populations — health risk rises at lower BMIs, which is why the WHO Asia-Pacific thresholds sit at 23 (overweight) and 25 (obesity).

Waist circumference, waist-to-height ratio and a body-fat estimate are better individual measures. Use BMI as a first-pass screen, not the final word.

BMI for children and pregnant women

The adult bands above do notapply to children, teenagers under 20, or pregnant women. Children use age- and sex-specific BMI percentiles from CDC or WHO growth charts — the same BMI number means different things at different ages. During pregnancy, weight gain is expected and BMI stops being meaningful; obstetric guidance uses pre-pregnancy BMI plus expected gestational weight gain. If either situation applies, this tool isn't the right one — ask a paediatrician or obstetrician.

Medical disclaimer. This calculator is general health information and is not a substitute for personalised medical advice. If you're managing a clinical condition, taking medication, or making major changes to diet or training, talk to a qualified healthcare professional first.

How it works

Formula: BMI = weight (kg) ÷ height² (m). A reading of 22.4 means you weigh 22.4 kg for every square metre of height.

The WHO global classification uses 18.5 / 25 / 30 cut-offs. The Asia-Pacific standard, adopted by the WHO Expert Consultation in 2004, lowers “overweight” to 23 and obesity to 25 — because Indian and other Asian bodies tend to accumulate visceral fat and develop cardiometabolic risk at a lower BMI than European populations.

Limitations: BMI doesn’t distinguish muscle from fat, and it doesn’t tell you where the fat is distributed. Athletes and very muscular people may read as “overweight” despite having low body fat. Use the Body Fat % calculator for a more complete picture.

Frequently asked questions

  • Is BMI reliable for athletes and muscular people?

    Not on its own. BMI counts all weight equally and can't tell muscle from fat, so very muscular people often read as 'overweight' despite low body fat. Pair it with a body-fat or waist measurement for a clearer picture.

  • Why does this calculator use lower Asia-Pacific thresholds?

    The WHO Expert Consultation recommended lower cut-offs for Asian populations because Indian and other Asian bodies tend to accumulate visceral fat and develop cardiometabolic risk at a lower BMI. The Asia-Pacific standard sets overweight at 23 and obesity at 25.

  • What is a healthy BMI range?

    Under the WHO global classification, 18.5 to 24.9 is considered the healthy range. BMI is a screening tool, not a diagnosis — a reading outside this range is a prompt to look closer, not a verdict on your health.