Ideal Weight Calculator
Healthy Weight: 128.9 – 174.2 lb
- Robinson (1983)
- 156.5 lb
- Miller (1983)
- 155.0 lb
- Devine (1974)
- 160.9 lb
- Hamwi (1964)
- 165.3 lb
- Healthy BMI range (18.5–25)
- 128.9 – 174.2 lb
What this ideal weight calculator does
“Ideal weight” is not a single number. Several formulas estimate a reference weight from height and sex, and they can disagree by several pounds. This calculator shows four common formulas — Robinson, Miller, Devine, and Hamwi — and a healthy weight range based on a BMI of 18.5 to 25.
The formulas were developed for different purposes, including drug dosing and clinical reference. They are not a personal target or a measure of health.
How to use this calculator
- Choose US or metric units.
- Enter age and sex.
- Enter your height. Age is shown for context but the four formulas use height and sex.
- Click Calculate to see each formula result and the healthy BMI range.
The default example is a 25-year-old man who is 5 ft 10 in tall.
Ideal weight formulas
For height above 5 feet, the formulas add a fixed amount per inch. Below 5 feet, the same per-inch amount is subtracted.
| Formula | Men | Women |
|---|---|---|
| Robinson (1983) | 52 kg + 1.9 kg/inch | 49 kg + 1.7 kg/inch |
| Miller (1983) | 56.2 kg + 1.41 kg/inch | 53.1 kg + 1.36 kg/inch |
| Devine (1974) | 50 kg + 2.3 kg/inch | 45.5 kg + 2.3 kg/inch |
| Hamwi (1964) | 48 kg + 2.7 kg/inch | 45.5 kg + 2.2 kg/inch |
The healthy BMI range is:
Low weight = 18.5 × height(m)²
High weight = 25 × height(m)²
What the results mean
- Robinson, Miller, Devine, Hamwi: four reference estimates. For the default example they are 156.5, 155.0, 160.9, and 165.3 lb.
- Healthy BMI range: the weight range that corresponds to a BMI of 18.5 to 25 at your height. For the default example it is 128.9–174.2 lb.
A single “ideal” number can be misleading. The range is generally more useful than any one formula.
Assumptions and limitations
The formulas use height and sex only. They do not account for frame size, muscle mass, body composition, age-related changes, pregnancy, or medical conditions. They were not designed as personal weight-loss targets.
Athletes and people with very high muscle mass may be healthy above the BMI-based range. Older adults may be healthy at a different weight. Use the results as reference points, not as a diagnosis or a goal set by someone else.
Frequently asked questions
Why do the formulas give different results?
They were derived from different populations and for different purposes. The differences are expected, especially at taller heights.
Which formula is best?
There is no single best formula for everyone. Devine is common in clinical settings; Robinson and Miller are often used in research. The healthy BMI range gives a broader context.
Does age affect ideal weight?
The four formulas do not use age. Body composition and health risks change with age, so a clinician may interpret the same weight differently for a younger and an older adult.
Is the healthy BMI range a target?
No. It is a reference range. A healthcare professional can help interpret it alongside your medical history, body composition, and lifestyle.
Reference table
Common ideal-weight formulas
These formulas use height above 5 feet (60 inches) and are historical reference values, not individualized medical targets.
| Formula | Ideal Weight |
|---|---|
| Devine (1974) | Men: 50 kg + 2.3 kg per inch over 5 ft. Women: 45.5 kg + 2.3 kg per inch over 5 ft. |
| Robinson (1983) | Men: 52 kg + 1.9 kg per inch over 5 ft. Women: 49 kg + 1.7 kg per inch over 5 ft. |
| Miller (1983) | Men: 56.2 kg + 1.41 kg per inch over 5 ft. Women: 53.1 kg + 1.36 kg per inch over 5 ft. |
| Hamwi (1964) | Men: 48 kg + 2.7 kg per inch over 5 ft. Women: 45.5 kg + 2.2 kg per inch over 5 ft. |
BMI-based healthy weight ranges are often more useful than a single ideal-weight number. Body composition, frame size, age, and health status also matter.
Source
References:
Disclaimer
This calculator is for informational and educational purposes only. It is not medical advice or a personalized weight goal. Discuss weight and health goals with a qualified clinician or registered dietitian.