BMI Calculator
With weight 90.718474 kg, height 182.88000000000002 cm, bmi comes to 27.1 — body mass index. It is reached in 9 steps, the last of which is 90.718474 / pow(1.8288, 2), and each one is printed on the page with its numbers filled in. The formula is the one published by CDC, not an approximation fitted to it.
Body mass index from height and weight in either metric or US units, with the CDC category cut-offs.
Formula and sources checked · How we check
Weight 200lbs, Height 6ft
27.1
Body mass index for the inputs in this link. Editing a field recomputes the calculator below; this figure holds the answer the page was loaded with.
It is written into the HTML rather than drawn by a script, so a search engine reading this page without running JavaScript still finds an answer.
- Body mass index
90.718474 / pow(1.8288, 2)27.125 kg/m²- Healthy-range weight, low end
18.5 * pow(1.8288, 2)61.873 kg- Healthy-range weight, high end
24.9 * pow(1.8288, 2)83.278 kg- BMI Prime — your BMI against the upper healthy limit
27.124598 / 251.085- Ponderal index
90.718474 / pow(1.8288, 3)14.832 kg/m³- Weight worth one BMI point at your height
pow(1.8288, 2)3.345 kg- Weight where the overweight band starts
25 * pow(1.8288, 2)83.613 kg- Weight where the obese band starts
30 * pow(1.8288, 2)100.335 kg- Weight between you and the nearest edge of the healthy band
90.718474 - 83.2782857.44 kg
Ask about this in the chatBMI Chart by Weight
Worked example
165 lbs at 5'11" is a BMI of 23.0, inside the 18.5–24.9 healthy band. The band itself spans 133–178 lbs at that height, which is a 45 lb window — BMI is a screening tool, not a target weight.
How to work it out yourself
- 1.Weigh yourself first thing in the morning, and measure height without shoes.
- 2.Convert to metric: kilograms and meters. 1 lb is 0.4536 kg and 1 in is 2.54 cm.
- 3.Divide the weight in kilograms by your height in meters squared.
- 4.Compare against the CDC bands — under 18.5, 18.5–24.9, 25–29.9, 30 and above — and treat the result as a screen, not a target.
BMI at 5 ft 9 in by weight
| Weight (kg) | Body mass index |
|---|---|
| 120 lbs | 16.7 |
| 140 lbs | 19.5 |
| 160 lbs | 22.3 |
| 180 lbs | 25.1 |
| 200 lbs | 27.9 |
| 220 lbs | 30.7 |
| 240 lbs | 33.5 |
At a fixed height of 175 cm. Roughly 7 lb moves BMI by one point at this height.
The formula
- Body mass index
90.718474 / pow(1.8288, 2) - Healthy-range weight, low end
18.5 * pow(1.8288, 2) - Healthy-range weight, high end
24.9 * pow(1.8288, 2) - BMI Prime — your BMI against the upper healthy limit
27.124598 / 25 - Ponderal index
90.718474 / pow(1.8288, 3) - Weight worth one BMI point at your height
pow(1.8288, 2) - Weight where the overweight band starts
25 * pow(1.8288, 2) - Weight where the obese band starts
30 * pow(1.8288, 2) - Weight between you and the nearest edge of the healthy band
90.718474 - 83.278285
Source: CDC — about adult BMI, NHLBI — body mass index and health risk, WHO — obesity and overweight, and the BMI classification
Questions people actually ask
- What are the categories?
- CDC adult cut-offs: under 18.5 underweight, 18.5–24.9 healthy, 25.0–29.9 overweight, 30.0 and above obese. They apply to adults 20 and older; children use age- and sex-specific percentiles instead.
- Why does BMI misclassify athletes?
- It uses total mass and cannot distinguish muscle from fat. A 6'0" 220 lb athlete at 10% body fat scores 29.8 — "overweight" — on the same number as a sedentary person at 30% body fat.
- What is BMI Prime?
- Your BMI divided by 25, the top of the healthy band. It turns the index into a plain ratio: 1.00 is exactly at the upper limit, 0.90 is 10% under it, 1.20 is 20% over. The same information as BMI, in the form people actually want it — how far from the line am I.
- What is the ponderal index?
- Weight divided by height cubed rather than squared. BMI’s squared term is an approximation that reads high for tall people and low for short ones; the ponderal index scales with volume instead, which is why paediatricians and studies of very tall or very short adults prefer it. Typical adult values run 11 to 15 kg/m³.
- Does BMI work for children?
- Not with these cut-offs. Children and teenagers aged 2 to 19 are read against age- and sex-specific percentile curves, because body composition changes through growth — the 85th percentile is where "overweight" begins, not a fixed number.
- What should I use instead?
- Waist circumference and waist-to-height ratio track metabolic risk more closely. A waist under half your height is the usual screening threshold, and it captures the visceral fat BMI is blind to.
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- Stones and Pounds ConverterA body weight in kilograms as stones and pounds, the way a British scale reads it — with the remainder shown rather than folded into a decimal.
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Part of a job
- Losing weight — 6 pages, in the order the questions arrive
Where this one stops
Worked out already
The same calculator with the numbers filled in. Each one computes on the server, so the answer is in the page rather than waiting on a click.
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