BMI Calculator
Body Mass Index from height and weight.
Runs entirely in your browser — nothing you enter is uploaded or sent to a server.
BMI is a rough screening number, not a diagnosis — it can't tell muscle from fat and doesn't suit athletes, pregnancy, children or older adults. For Indians the commonly used cut-offs are lower (overweight from about 23 rather than 25), so read your category with that in mind. It isn't medical advice — talk to a doctor about what's right for you. Read our full disclaimer.
About this tool
Body Mass Index (BMI) is a quick screening number from your height and weight — BMI = weight in kilograms ÷ height in metres squared — that sorts adults into underweight, normal, overweight, and obese ranges. This tool works in metric or imperial units and shows both your category and the healthy-weight range for your height. It's a useful, free first check, but a population-level screen rather than a diagnosis: it can't tell muscle from fat or where fat sits, so read it alongside how you feel and, for anything health-related, a professional's view.
Example
70 kg at 175 cm gives a BMI of about 22.9 — in the normal range (18.5–24.9).
How to use
- 1Choose metric or imperial units.
- 2Enter your weight and height.
- 3Read your BMI, its category, and a healthy-weight range.
Features
- Metric or imperial input.
- BMI value, category, and healthy-weight range.
- Based on the standard WHO adult categories.
Frequently asked questions
What is a healthy BMI range?
For adults, the standard WHO ranges are: under 18.5 is underweight, 18.5–24.9 is the normal range, 25–29.9 is overweight, and 30 or above is obese. The tool shows the weight range that keeps your height in the normal band.
Is BMI accurate for everyone?
No — it's a rough screen. BMI can't tell muscle from fat or account for where fat is stored, so it may read too high for athletes and very muscular people, and can underestimate body fat in older adults. Treat it as one general indicator, not the whole picture.
Do the healthy ranges differ by ethnicity?
They can. The BMI tied to the same health risk varies by population — many guidelines use a lower overweight threshold (around 23) for people of South Asian descent, for example. This tool shows the standard WHO cut-offs; check what your local guidance recommends.
Does BMI work for children or during pregnancy?
Not with these adult ranges. Children and teens are assessed on age- and sex-specific percentile charts, and BMI isn't meaningful during pregnancy. This tool is intended for non-pregnant adults.
Is this medical advice?
No — it's general information for a quick self-check. BMI doesn't diagnose anything; for decisions about your weight or health, talk to a qualified professional. See our Disclaimer.
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