BMI of a 165 cm, 51 kilogram person

What is the BMI of a man or woman who weighs 51 kilos and is 165 centimeters tall?
cm
kg
BMI = 18.73
Note: BMI is the same for men and women.

Am I Overweight?

Here are the BMI standards as set by the World Heath Organization:

BMICategory
< 18.5Underweight
18.5 - 25Healthy Weight
25 - 30Overweight
> 30Obese

In the United States, the average BMI for adults is 28.8.

BMI Formula

Metric
BMI = kg / m2

Imperial
BMI = (lbs * 0.45359237) / (inches * 0.0254)2

Simplified
BMI = 703 * lbs / inches2

Is BMI Worth Using?

Body Mass Index is a very simplistic method of determining whether a person is overweight. It does not taken into account a person's frame, gender, or muscularity. Furthermore, at least one study has suggested that slightly overweight people may live longer than people in the "normal" range.

Nevertheless, BMI is highly correlated with body fat % and is a decent enough yardstick of a healthy weight.

Body fat estimates for a person with a BMI of 18.73
These are rough estimates based on a formula, and do not reflect differences in muscularity, body types, etc...
Age Male Female
18 10.4% 21.2%
19 10.6% 21.4%
20 10.9% 21.7%
21 11.1% 21.9%
22 11.3% 22.1%
23 11.6% 22.4%
24 11.8% 22.6%
25 12.0% 22.8%
26 12.3% 23.1%
27 12.5% 23.3%
Age Male Female
28 12.7% 23.5%
29 12.9% 23.7%
30 13.2% 24.0%
31 13.4% 24.2%
32 13.6% 24.4%
33 13.9% 24.7%
34 14.1% 24.9%
35 14.3% 25.1%
36 14.6% 25.4%
37 14.8% 25.6%
Age Male Female
38 15.0% 25.8%
39 15.2% 26.0%
40 15.5% 26.3%
41 15.7% 26.5%
42 15.9% 26.7%
43 16.2% 27.0%
44 16.4% 27.2%
45 16.6% 27.4%
46 16.9% 27.7%
47 17.1% 27.9%
Age Male Female
48 17.3% 28.1%
49 17.5% 28.3%
50 17.8% 28.6%
51 18.0% 28.8%
52 18.2% 29.0%
53 18.5% 29.3%
54 18.7% 29.5%
55 18.9% 29.7%