Ideal Weight Calculator
Enter your sex and height to see estimates from four classic ideal body weight formulas, compared with the weight range for a BMI of 18.5 to 24.9.
Last updated November 2, 2026
Used only by the formula
Result
134.3 lb to 138.1 lb by the four formulas
| Measure | Value |
|---|---|
| Devine (1974) | 135.8 lb |
| Robinson (1983) | 134.3 lb |
| Miller (1983) | 138.1 lb |
| Hamwi (1964) | 134.3 lb |
| Weight at BMI 18.5 to 24.9 | 118.1 lb to 159 lb |
These formulas use only height and sex, so they ignore build, muscle and age. Use them as a rough reference, not a target. General estimate only, not medical advice. Talk to a qualified health professional about your own situation.
Show the work
Formula: Each formula: base weight (kg) + kg per inch × inches of height above 5 ft (60 in).
- You entered 5 ft 7 in (female), which is 170.2 cm = 67 in. Inches over 60: 7.
- Devine: 45.5 + 2.3 × 7 = 135.8 lb.
- Robinson: 49 + 1.7 × 7 = 134.3 lb.
- Miller: 53.1 + 1.36 × 7 = 138.1 lb.
- Hamwi: 45.5 + 2.2 × 7 = 134.3 lb.
- Lowest and highest of the four give the range.
Result: 134.3 lb to 138.1 lb by the four formulas
How ideal weight formulas work
Devine: 50 kg (men) or 45.5 kg (women) + 2.3 kg for every inch over 5 feet
All four formulas start from a base weight at 5 feet and add a fixed amount for each inch above it. Devine (1974) adds 2.3 kg per inch. Robinson (1983) adds 1.9 kg for men and 1.7 kg for women from bases of 52 kg and 49 kg. Miller (1983) uses 56.2 kg and 53.1 kg plus 1.41 and 1.36 kg per inch. Hamwi (1964) uses 48 kg and 45.5 kg plus 2.7 and 2.2 kg per inch.
The formulas were written for clinical use, not as health targets, and they ignore frame size, muscle and age. They only apply from 5 feet (152.4 cm) up. Treat them as rough reference points alongside the BMI-based range.
See how we calculate for the formulas, sources and review schedule behind every calculator.
Also useful alongside this calculator: BMI Calculator, Protein Calculator and Pace Calculator.
This is an estimate, not medical advice
This calculator gives a general estimate from the published methods listed under Sources. It does not diagnose anything or replace advice from a doctor, dietitian or other qualified health professional, and individual needs differ. This page has not been reviewed by a medical professional.
Sources
Official and primary sources for the statements on this page. Their authors have not reviewed or endorsed this page.
- Robinson JD, Lupkiewicz SM, Palenik L, Lopez LM, Ariet M. Determination of ideal body weight for drug dosage calculations. Am J Hosp Pharm 1983;40(6):1016-1019. Source of the Robinson formula, derived from height-weight tables for drug dosing. The abstract gives 51.65 kg + 1.85 kg per inch over 5 feet for men and 48.67 kg + 1.65 kg for women
- Pai MP, Paloucek FP. The origin of the "ideal" body weight equations. Ann Pharmacother 2000;34(9):1066-1069. Explains that Devine’s equations came into use because some drug pharmacokinetics tracked ideal body weight, and that the equations match an older height-weight-table rule
The coefficients on this page are the versions commonly published for Devine, Robinson, Miller and Hamwi. For Robinson they are rounded (52 + 1.9 and 49 + 1.7) and differ slightly from the paper’s abstract above. We could not open the original Devine, Miller (a 1983 letter in the same journal) or Hamwi (1964) publications, so those three are not cited as sources.
These formulas were written for drug dosing and are defined from 5 feet upward. They are not health targets.
How to use the Ideal Weight Calculator
- Choose units and sex.
- Enter your height (5 feet or taller).
- Compare the four formula results with the BMI-based range, then use Copy, Print or Share.
Worked example
A woman who is 5 ft 7 in is 7 inches over 5 feet. Devine gives 45.5 + 2.3 × 7 = 61.6 kg (135.8 lb). The other formulas give 134 to 138 lb, and a BMI of 18.5 to 24.9 corresponds to about 118 to 159 lb.
| Formula | Weight |
|---|---|
| Devine | 135.8 lb |
| Robinson | 134.3 lb |
| Miller | 138.1 lb |
| Hamwi | 134.3 lb |
| BMI 18.5 to 24.9 | 118 to 159 lb |
Frequently asked questions
Which ideal weight formula is the best?
None is best. They give similar answers for average heights, and each is only a rough guide.
Why is there a minimum height?
The formulas add weight per inch over 5 feet, so they do not apply below that height.
Is my ideal weight the weight I should aim for?
Not necessarily. A healthy weight depends on build, muscle, age and health, so ask a health professional before setting a target.
Why do the results differ from the BMI range?
The formulas give one number from height and sex, while the BMI range is wide and does not consider sex.
Are my numbers stored or sent anywhere?
No. The calculation runs in your browser and nothing you enter is saved or uploaded.