BMI for 6′5″ and 100 lb
BMI = 11.9 (Underweight (severe thinness))
An adult who is 6′5″ tall and weighs 100 lb has a body mass index of 11.9. The healthy weight range for this height (BMI 18.5–24.9) is about 156 lb to 210 lb.
For adults 20 and over. BMI is a screening measure, not a diagnosis.
How this BMI is calculated
- Height in inches: 6 × 12 + 5 = 77 in; squared: 5,929.
- BMI = 703 × weight ÷ height²: 703 × 100 ÷ 5,929 = 11.9.
BMI Prime (BMI ÷ 25) is 0.47: values above 1.0 are above the healthy range.
At this height, a weight of 156 lb or more corresponds to a BMI of 18.5 or above.
BMI chart for 6′5″
| 100 lb | 11.9 | Underweight (severe thinness) |
| 110 lb | 13.0 | Underweight (severe thinness) |
| 120 lb | 14.2 | Underweight (severe thinness) |
| 130 lb | 15.4 | Underweight (severe thinness) |
| 140 lb | 16.6 | Underweight (moderate thinness) |
| 150 lb | 17.8 | Underweight (mild thinness) |
| 160 lb | 19.0 | Healthy weight |
| 170 lb | 20.2 | Healthy weight |
| 180 lb | 21.3 | Healthy weight |
| 190 lb | 22.5 | Healthy weight |
| 200 lb | 23.7 | Healthy weight |
| 210 lb | 24.9 | Healthy weight |
| 220 lb | 26.1 | Overweight |
| 230 lb | 27.3 | Overweight |
| 240 lb | 28.5 | Overweight |
| 250 lb | 29.6 | Overweight |
| 260 lb | 30.8 | Obesity class I |
| 270 lb | 32.0 | Obesity class I |
| 280 lb | 33.2 | Obesity class I |
| 290 lb | 34.4 | Obesity class I |
| 300 lb | 35.6 | Obesity class II |
BMI categories for adults (WHO)
- Under 18.5: underweight
- 18.5–24.9: healthy weight
- 25–29.9: overweight
- 30 or more: obesity (class I 30–34.9, II 35–39.9, III 40+)
For people of Asian descent, health risks rise at lower BMIs, and 23 and 27.5 are often used as action points. BMI does not separate muscle from fat, so very muscular people can have a high BMI without excess fat. It is a screening tool; talk to a health professional about your own situation.
Nearby heights
Frequently asked questions
What is the BMI of someone 6′5″ and 100 lb?
A BMI of 11.9, which the WHO classifies as Underweight (severe thinness) for adults.
How is BMI calculated?
BMI is your weight in kilograms divided by your height in meters squared: BMI = kg ÷ m². In US units, BMI = 703 × pounds ÷ inches².
What is a healthy BMI?
For adults the World Health Organization classes 18.5 to 24.9 as a healthy weight, 25 to 29.9 as overweight and 30 or more as obesity. For people of Asian descent, lower cut-offs (23 and 27.5) are often used for health risk.
Is BMI accurate?
BMI is a quick screening measure, not a diagnosis. It does not distinguish muscle from fat, so it can overestimate fat in athletes and underestimate it in older adults. Waist size and other checks give a fuller picture.