Ideal Weight Calculator
What should you weigh? See the healthy weight range for your height, and what the classic "ideal weight" formulas say, with an honest note on what they're good for.
Your details
Your results
Enter your sex and height to see a healthy weight range.
Healthy weight range for your height
A BMI of 18.5 to 24.9, the WHO's healthy range for adults.
| Formula | Weight |
|---|---|
| Devine (1974) | |
| Robinson (1983) | |
| Miller (1983) | |
| Hamwi (1964) |
How to use it
- Choose your units, then enter your sex and height.
- Read your healthy weight range. It's the weight that gives a BMI of 18.5 to 24.9 at your height.
- The table shows four classic formulas for comparison. They don't account for muscle, so lifters often weigh more and are still healthy.
How it's calculated
Healthy weight range. From the WHO’s adult BMI classification, where BMI 18.5 to 24.9 is the healthy range:
- lowest weight = 18.5 × height (m)²
- highest weight = 24.9 × height (m)²
Classic formulas. The Robinson row uses the coefficients in the original paper. Each formula starts at 5 ft (60 in) and adds a fixed amount for every inch above it:
| Formula | Men | Women |
|---|---|---|
| Devine (1974) | 50 kg + 2.3 kg per inch | 45.5 kg + 2.3 kg per inch |
| Robinson (1983) | 51.65 kg + 1.85 kg per inch | 48.67 kg + 1.65 kg per inch |
| Miller (1983) | 56.2 kg + 1.41 kg per inch | 53.1 kg + 1.36 kg per inch |
| Hamwi (1964) | 106 lb + 6 lb per inch | 100 lb + 5 lb per inch |
Example: a man of 5 ft 10 in (70 in) gets 50 + 2.3 × 10 = 73 kg with Devine.
Limits. None of these formulas, nor BMI, knows how much of your weight is muscle. They’re a starting point for a conversation, not a goal. Below 5 ft, only the BMI range is shown.
Sources
- World Health Organization (2000). Obesity: preventing and managing the global epidemic. Technical Report Series 894. Adult BMI classification.
- Pai, M. P., & Paloucek, F. P. (2000). The origin of the 'ideal' body weight equations. Annals of Pharmacotherapy, 34(9), 1066–1069.
- Robinson, J. D., et al. (1983). Determination of ideal body weight for drug dosage calculations. American Journal of Hospital Pharmacy, 40(6), 1016–1019.
Questions
What is my ideal weight?
There isn't one exact number. Health organizations use a range, the weights that give a BMI of 18.5 to 24.9 at your height. Where you feel and perform best inside that range depends on your build and how much muscle you carry.
Why do the formulas give different answers?
Each formula was fitted to different data, from different decades. Devine (1974) was made to dose a medicine; Robinson and Miller (1983) refit it using insurance tables; Hamwi (1964) came from a diabetes nutrition guide. None was designed as a health target.
I lift and I'm above the range. Is that a problem?
Not necessarily. BMI and these formulas can't tell muscle from fat. A waist measurement or a body fat estimate says more for lifters. Try the Waist to Height Ratio Calculator or the Body Fat Calculator.
Why does it say "not defined under 5 ft"?
The classic formulas start at 5 ft (152 cm) and add weight for every inch above it. Below that height, they were never defined. The BMI range works at any adult height.
Updated November 9, 2026.