Nutrition – Body weight 101

Web MasterNutrition Counseling

Heidi Nebel

Nutrition Notes

By Heidi Nebel Ochsner, MS, CN, RD
Tummy Temple’s Registerd Dietitian

Body weight 101:
How do I calculate my ideal body weight?

Weight Scale
Image by Sylvar


To calculate your ideal body weight (IBW) you can use this simple Hamwi equation:

Hamwi –

Female First 5 feet = 100lbs + 5lbs for each additional Inch
Male First 5 feet = 106 lbs + 6lbs for each additional Inch

Both are expressed as a range + OR – 10% to consider frame size of the individual.

For example: A female who is 5’8” tall has and ideal body weight = 100lbs + (5lbs x 8) = 100 + 40 = 140 lbs

You must remember this is the middle of an ideal body range. Therefore, you must add and subtract 10% to this middle number to get the full range of ideal body weight.

So… 140lbs + or – 10%
10% of 140lbs = 14lbs
140lbs + 14lbs = 158lbs
140lbs – 14lbs = 126lbs

Therefore the ideal body weight range for this example is from 126lbs – 158lbs. This takes into account differences in body frame.

It is important to note that ideal body weight is for adults and does not work for people less than 5 feet tall.
Metric system conversions: Conversions: Lbs/2.2 = kilograms (kg)
Inches x 2.54 = Centimeters (cm)