BMI Calculator for Men
Adult BMI calculator for ages 20+, with CDC categories, NICE guidance, limitations and next steps. Measurements are processed in your browser; site analytics are separate.
For adults age 20 or older. Ages 2–19 need the CDC BMI-for-age percentile calculator. Do not use this tool during pregnancy or if you have a diagnosed or suspected eating disorder. Ask a clinician, midwife, or eating-disorder service for individual support.
The starting values are an example. Replace them with your own measurements.
Your BMI
– kg/m²
JavaScript requiredCategories use the unrounded BMI. The number shown is rounded to one decimal place.
The calculator code processes the age, height, and weight entered on this page. It does not store or send those entries. Separate site analytics may use browser storage or process page-use data; see the privacy policy.
MethodBMI is kg/m². This tool converts pounds and inches to metric before calculating; 703 × lb/in² is the conventional rounded formula. Standard adult categories follow CDC guidance for ages 20+. Categories use the unrounded result; display rounds to one decimal. Source evidence checked 16 September 2026.
How to use this adult BMI calculator
Enter an age of 20 or older, then add weight and height in metric or imperial units. Switching units converts the same physical measurements. Returning to the unit you typed restores your original entry. The tool rejects blank, negative, out-of-range, and invalid ft/in components before showing a result.
The formula and standard adult categories
BMI is weight in kilograms divided by height in metres squared. For a manual imperial calculation, the conventional formula is 703 times pounds divided by inches squared. The factor 703 is rounded. This tool instead converts pounds and inches to kilograms and metres using standard unit conversions, then calculates BMI. Switching units therefore preserves the result; a hand calculation using 703 can differ slightly near a category boundary. The CDC adult categories are below 18.5 underweight, 18.5 to below 25 healthy weight, 25 to below 30 overweight, and 30 or above obesity. Obesity classes begin at 30, 35, and 40.
The category is based on the unrounded BMI. The displayed value is rounded to one decimal place. A raw BMI of 24.95 therefore displays as 25.0 but remains in the standard healthy-weight category; 29.95 displays as 30.0 but remains in the overweight category. This convention avoids moving a result across a clinical boundary solely because of display rounding.
Who should not use this result
This calculator applies the CDC adult method for ages 20 and older. For ages 2–19, BMI must be interpreted as a sex-specific BMI-for-age percentile. During pregnancy, or with a diagnosed or suspected eating disorder, do not use this generic result to guide weight decisions. Contact a clinician, midwife, or eating-disorder service instead. If a condition affects your height, ask a clinician how to assess your weight; the NHS adult BMI tool excludes this situation.
Ethnicity-specific interpretation
The formula does not change by ethnicity, but one guideline uses lower practical thresholds for some groups. NICE NG246 uses 23 to 27.4 for overweight and 27.5 or above for obesity in people with a South Asian, Chinese, other Asian, Middle Eastern, Black African, or African-Caribbean background. These are population-level cardiometabolic-risk thresholds for clinical assessment. They do not mean everyone in a listed group has the same individual risk, and they do not change the calculator's standard CDC label.
Healthy weight range by exact imperial height
Each row uses the exact ft/in height shown; the centimetre value is approximate. The intervals come from the continuous standard healthy BMI range, 18.5 to below 25. The displayed endpoints are rounded inward, so every listed weight remains inside that interval. This table is a reference, not a target or treatment plan.
| Exact height | Healthy-weight interval (lb) | Healthy-weight interval (kg) |
|---|---|---|
| 5 ft 5 in (about 165.1 cm) | 112–150 lb | 50.5–68.1 kg |
| 5 ft 6 in (about 167.6 cm) | 115–154 lb | 52.0–70.2 kg |
| 5 ft 7 in (about 170.2 cm) | 119–159 lb | 53.6–72.4 kg |
| 5 ft 8 in (about 172.7 cm) | 122–164 lb | 55.2–74.5 kg |
| 5 ft 9 in (about 175.3 cm) | 126–169 lb | 56.9–76.7 kg |
| 5 ft 10 in (about 177.8 cm) | 129–174 lb | 58.5–79.0 kg |
| 5 ft 11 in (about 180.3 cm) | 133–179 lb | 60.2–81.3 kg |
| 6 ft 0 in (about 182.9 cm) | 137–184 lb | 61.9–83.6 kg |
| 6 ft 1 in (about 185.4 cm) | 141–189 lb | 63.7–85.9 kg |
| 6 ft 2 in (about 188.0 cm) | 145–194 lb | 65.4–88.3 kg |
| 6 ft 3 in (about 190.5 cm) | 149–200 lb | 67.2–90.7 kg |
| 6 ft 4 in (about 193.0 cm) | 152–205 lb | 69.0–93.1 kg |
Limits of BMI
BMI is a screening measure, not a diagnosis. It does not distinguish fat, muscle, and bone or directly measure central adiposity. A person with high muscle mass can fall in a higher standard category. NICE advises caution for high-muscle-mass adults and for people age 65 or older, where health conditions and physical function also affect interpretation.
For adults with BMI below 35, NICE recommends using waist-to-height ratio alongside BMI to add central-adiposity context. Neither result establishes an individual diagnosis.
What to do next
If your BMI is below 18.5, or you are losing weight without trying, speak with a clinician. A low BMI can be associated with malnutrition risk, and ongoing unintentional weight loss needs assessment. Do not use this tool to prescribe weight gain or loss for yourself.
If your BMI is elevated, check the entry and consider waist measurement. A clinician can assess other health conditions and factors that affect your weight, then decide which examinations or tests are appropriate. The calculator does not prescribe weight loss.
Frequently asked questions
Is BMI accurate for men?
BMI is a rough screening measure based only on height and weight. It cannot distinguish fat, muscle, and bone or directly measure central adiposity, so it needs context rather than use as a diagnosis.
Who should not use this adult BMI calculator?
It is for adults age 20 or older under the CDC method. Ages 2–19 need sex-specific BMI-for-age percentiles. Do not use this generic result during pregnancy or with a diagnosed or suspected eating disorder; ask a clinician, midwife, or eating-disorder service for individual support. If a condition affects your height, ask a clinician how to assess your weight.
What is a healthy BMI for a man?
The standard CDC healthy-weight category is 18.5 to below 25 for adults 20 or older. NICE uses lower practical overweight and obesity thresholds for specified ethnic backgrounds because cardiometabolic risk can occur at a lower BMI. Neither set of thresholds gives an individual diagnosis.
Why can the displayed BMI and category look different at a boundary?
The category uses the unrounded BMI, while the number shown is rounded to one decimal place. A raw BMI of 24.95 displays as 25.0 but stays in the standard healthy-weight category; 29.95 displays as 30.0 but stays in the overweight category.
Are my calculator entries stored?
The calculator code does not store or send the age, height, or weight you enter. That statement applies to the calculator entries, not the whole website. Separate site analytics may use browser storage or process page-use data; see the privacy policy.