What is BMI Chart and Body Mass Index?
A BMI Chart or Body Mass Index Chart can be a useful tool for visualizing the ranges for underweight, healthy weight, overweight, and obesity based on a person’s height. The simplicity of the BMI formula has made it extremely popular as an initial diagnosing tool for determining a person’s healthy body weight. The BMI chart formula does have its shortcomings because it does not take into account age, frame size, gender, or muscularity.
The BMI Formula
BMI is defined as a person’s weight divided by the square of a person’s height, using the metric units kg/m^2.
- Metric Units: BMI = Weight[kg] / ( Height[m] x Height[m] )
- English Units: 703 x Weight[lb] / ( Height[in] x Height[in] )
Children BMI chart
BMI is calculated the same for children, as for adults. But the criteria for determining the “normal” weight are different. Instead of certain BMI thresholds, the BMI percentile is used to compare with other children of the same age and gender. Just like the growth charts “Weight-for-Age”, “Growth to Age” and “Head Circles to Age,” there are also BMI-for-Age charts.
Download the BMI-for-Age Chart for Boys from cdc.gov.
Download the BMI-for-Age Chart for Girls from cdc.gov.
For children, the weight status category (underweight, healthy weight, overweight, and obese) is defined based on the BMI percentile (less than the 5th percentile, 5th to less than the 85th, 85th to less than the 95th, and equal to or greater than 95th, respectively). See BMI for Children and Teens on the cdc.gov website for the official information.