Ideal Weight Calculator - Find Your Healthy Weight Range

What is Ideal Body Weight?

Ideal body weight (IBW) is a weight that is believed to be maximally healthful for a person based on height. While "ideal" weight varies by individual, several scientific formulas have been developed over the decades to estimate a healthy target weight. These formulas consider height and gender as primary factors.

Ideal Weight Formulas

Devine Formula (1974)

Originally developed for calculating drug dosages, the Devine formula became widely used for ideal body weight estimation:

Men: IBW = 50 kg + 2.3 kg × (height in inches − 60)
Women: IBW = 45.5 kg + 2.3 kg × (height in inches − 60)

Robinson Formula (1983)

A modification of the Devine formula with slightly different coefficients:

Men: IBW = 52 kg + 1.9 kg × (height in inches − 60)
Women: IBW = 49 kg + 1.7 kg × (height in inches − 60)

Miller Formula (1983)

Another variation that tends to give higher estimates:

Men: IBW = 56.2 kg + 1.41 kg × (height in inches − 60)
Women: IBW = 53.1 kg + 1.36 kg × (height in inches − 60)

Hamwi Formula (1964)

One of the earliest formulas, still commonly referenced:

Men: IBW = 48 kg + 2.7 kg × (height in inches − 60)
Women: IBW = 45.5 kg + 2.2 kg × (height in inches − 60)

BMI-Based Healthy Weight

The World Health Organization defines a healthy BMI range as 18.5 to 24.9 kg/m². This calculator also shows the weight range corresponding to these BMI values for your height, providing another perspective on healthy weight targets.

Limitations

These formulas were developed based on population averages and may not account for individual factors such as:

Muscle mass and body composition
Age and bone density
Ethnic and genetic variations
Frame size (small, medium, large)

Always consult with a healthcare provider for personalized health advice.

Frequently Asked Questions

What is ideal body weight?

Ideal body weight (IBW) is an estimate of a healthy weight for a given height. It has been used historically for medical dosages and as a general health guideline. However, 'ideal' varies significantly based on body composition, muscle mass, bone density, age, and frame size. The four formulas shown (Devine, Robinson, Miller, Hamwi) provide different estimates, and the average gives a balanced target. The healthy BMI range (18.5–24.9) offers an alternative evidence-based target.

Which ideal weight formula is most accurate?

No single formula is universally most accurate. The Devine formula (1974) is the most widely used but was originally developed for drug dosing, not weight goals. The Robinson formula (1983) tends to give slightly lower estimates, while the Miller formula (1983) gives higher estimates. The Hamwi formula (1964) is the oldest. Each formula has its limitations because they were developed based on population averages and don't account for individual differences in muscle mass, bone density, or body composition.

What is the healthy BMI range for my height?

The healthy BMI range of 18.5–24.9 corresponds to different weight ranges depending on your height. For a person who is 5'9" (175 cm), the healthy weight range is approximately 125–169 lbs (57–77 kg). The calculator above shows your specific healthy BMI-based weight range alongside the formula-based estimates. This provides both a formula-based target and an evidence-based healthy range.

Does frame size affect ideal weight?

Yes, frame size (small, medium, large) affects how weight is distributed on your body. People with larger frames have more bone mass and wider body structures, which can add 5-10 lbs to their ideal weight. The formulas shown in this calculator do not account for frame size, which is a known limitation. To estimate frame size, measure your wrist circumference or elbow breadth and compare to height-based charts.