U.S. or Metric Units
on this page.
Body Mass Index, or BMI, is commonly used to determine whether or not
a person is at a healthy weight. A BMI of 18.5 to 24.9 is considered healthy;
25 to 29.9 represents overweight, while a person with a BMI of 30 or greater
is said to be obese. These figures are said to be reliable in most cases,
except for the following:
Though BMI is still widely used in doctor’s offices (mainly
because it’s easy to measure and calculate), it is no longer
considered to be the most accurate way to determine whether a person
is normal, overweight, or obese, or even whether a person is healthy.
People with high BMIs may have low body fat, or vice versa. Waist
measurement (less than 35 inches for women, or 40 inches for men)
or waist-to-hip ratio are cited as more accurate alternatives.
The latter is determined by dividing the waist measurement (at the navel)
by the hip measurement (at the buttocks). A ratio greater than 0.85 for
women, or 0.9 for men, indicates too much belly fat. For more information,
see the following articles:
BMI is calculated by dividing the person’s weight in kilograms
by the square of his or her height in meters. For U.S. units, multiply
the weight in pounds by 703.08, then divide by the square of the height
in inches. For those not mathematically inclined, these online calculators
will prove useful. They should not, however, substitute for the advice of
a qualified health professional.
Useful height range is 4 to 8 feet.
Height in feet:
Weight in pounds:
Useful height range is 122 to 243 centimeters.
Height in centimeters:
Weight in kilograms: