BMI Calculator
BMI is your weight in kilograms divided by your height in metres squared. Enter your height and weight below and you'll get the number, the category it falls into, and — because the two disagree more often than people expect — how it reads under both the WHO standard and the Asian Indian one.
Enter your height and weight to see your BMI.
BMI is a screening number, not a diagnosis. It tells you how your weight compares to your height and nothing else — not how much of that weight is muscle, not where the fat sits, not how healthy you are. It is useful precisely because it is crude: it costs nothing, needs no equipment, and flags people worth looking at more closely.
Why your BMI category may be different in India
Most BMI calculators use one set of thresholds: under 18.5 is underweight, 18.5 to 25 is normal, 25 to 30 is overweight, and 30 or above is obese. Those are the WHO's international cut-offs, and they were derived largely from European-origin populations.
South Asian populations tend to develop the conditions BMI is screening for — type 2 diabetes, high blood pressure, cardiovascular disease — at lower BMIs than European-origin populations do. At the same BMI, South Asians generally carry more body fat and more of it around the abdomen and organs. A body that looks unremarkable on the scale can already be metabolically stressed.
For that reason, guidelines for Asian Indian adults use lower thresholds: 23 and above is overweight, 25 and above is obese. The WHO's own Asia-Pacific consultation similarly identified 23 as a point of increased risk. This calculator shows you both readings side by side rather than picking one for you.
The practical effect is a band between 23 and 25 where the two standards flatly disagree. A person at 175cm and 72kg has a BMI of 23.5 — comfortably "normal weight" internationally, and "overweight" under the Indian guidance. Neither number is wrong. They are answering slightly different questions about risk.
What BMI gets wrong
BMI has one input for body size and no way to tell tissue apart. That produces predictable failures, and it is worth knowing whether you are one of them before you take the number seriously.
- Muscular peopleMuscle is denser than fat. Someone who lifts seriously can post a BMI in the overweight range with low body fat. This is the most commonly cited flaw, though it applies to fewer people than the internet suggests.
- Older adultsMuscle mass tends to decline with age while fat increases. An older person can hold a stable BMI for years while their body composition changes underneath it.
- Where the fat sitsFat around the abdomen carries more metabolic risk than fat on the hips and thighs. BMI cannot distinguish the two, which is why waist measurement adds information BMI does not have.
- Very short or very tall peopleThe height-squared term does not scale perfectly across the full range of adult heights, so BMI tends to read slightly high for tall people and slightly low for short ones.
- Pregnancy, and childrenBMI as calculated here is for non-pregnant adults. Children and teenagers are assessed against age-and-sex percentile charts instead, not fixed cut-offs.
The measurement worth taking alongside it
If you only add one thing to BMI, make it your waist. Measure at the midpoint between the bottom of your ribs and the top of your hip bone, at the end of a normal breath out, with the tape snug but not compressing the skin.
A useful and easy rule is waist-to-height ratio: keep your waist under half your height. At 170cm that means a waist under 85cm. It needs no lookup table, applies across adult populations reasonably well, and captures the abdominal fat that BMI is blind to.
Taken together, the two numbers are far more informative than either alone. A normal BMI with a large waist is worth attention. A high BMI with a small waist and visible muscle usually is not.
What to do with the number
BMI is a starting point for a conversation, not a target to optimise. If yours falls outside the normal band, the useful next question is not "how do I move this number" but "what is driving it, and is it worth changing?"
If you decide it is, weight change comes down to energy balance over time, which means knowing roughly what you burn and roughly what you eat. The first half of that is what a TDEE calculator estimates; the second half is what food logging measures. Neither needs to be precise to be useful — they need to be consistent enough to show a direction.
And if your BMI is in the underweight band, that deserves the same attention as the other end. Unintentional weight loss, in particular, is worth raising with a doctor rather than solving with a meal plan.
BMI categories: WHO and Asian Indian cut-offs
The underweight threshold is the same in both. Everything above it differs.
| Category | WHO (international) | Asian Indian |
|---|---|---|
| Underweight | Below 18.5 | Below 18.5 |
| Normal weight | 18.5 – 24.9 | 18.5 – 22.9 |
| Overweight | 25.0 – 29.9 | 23.0 – 24.9 |
| Obese | 30.0 and above | 25.0 and above |
Asian Indian thresholds follow the consensus guidance for Asian Indian adults; the WHO Asia-Pacific consultation likewise flags 23 as a point of increased risk.
Frequently asked questions
What is a healthy BMI?
Under the WHO standard, 18.5 to 24.9 is classed as normal weight. Under the guidance used for Asian Indian adults it is 18.5 to 22.9. Both are population-level bands rather than individual targets — a single number cannot account for your muscle mass, age or body shape.
Which standard should I use, WHO or Indian?
If you are of South Asian ancestry, the lower thresholds are the more cautious reading and the one Indian clinical guidance uses. They are a prompt to look more closely, not a diagnosis. If your BMI lands between 23 and 25, that is exactly the band where the two standards disagree and where a waist measurement is worth taking.
Is BMI accurate for muscular people?
Often not. BMI cannot tell muscle from fat, so a well-muscled person can read as overweight while carrying low body fat. If that describes you, a body fat estimate is more informative than BMI.
Does BMI work differently for men and women?
The formula and the cut-offs are the same for both. Women generally carry a higher proportion of body fat than men at the same BMI, which is one more reason the number is a screening tool rather than a measure of body composition.
What BMI is considered obese?
30 and above under the WHO standard, and 25 and above under the Asian Indian guidance. Obesity is a clinical classification, and interpreting it properly involves more than one number — which is a conversation for a doctor, not a calculator.
How do I lower my BMI?
BMI moves when weight moves relative to height, and sustained weight change comes from a consistent energy deficit rather than a specific diet. Before changing anything it is worth establishing what you currently eat and roughly what you burn, so you are adjusting from a known starting point rather than guessing.
Can I have a normal BMI and still be unhealthy?
Yes. A normal BMI with a large waist, low muscle mass or poor metabolic markers is a recognised pattern. BMI screens for one thing — weight relative to height — and a normal result rules out only that one thing.
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Numbers are the easy part
A calorie target only does something once you know what you are actually eating. Describe your meal in plain language or send a photo, and Pulze estimates the calories and protein for it — including the food a generic database has never heard of.
Open the food trackerLast reviewed 25 August 2026. These calculators use published equations and give estimates, not measurements. This is general information, not medical advice — for decisions about your health, speak to a doctor or a registered dietitian.