What this calculator does
Ideal body weight formulas were developed for clinical purposes rather than as personal targets. The Devine formula, the most widely used, was published in 1974 to calculate medication dosages: not to tell anyone what they should weigh. The others followed as refinements on similar data.
All four are shown here because they disagree, sometimes by several kilograms at the same height. That disagreement is the most useful thing about the comparison: it demonstrates that there is no single correct weight for a given height, only a range that different methods place slightly differently.
The formula
Each formula starts from a base weight at 152.4 cm (five feet) and adds a fixed amount for every inch above that. They differ only in their base and increment, which is why they diverge more as height increases. The healthy BMI range is included as a broader, more modern reference.
| Term | Meaning |
|---|---|
| Devine | The 1974 clinical standard, still widely used for drug dosing. |
| Robinson | A 1983 revision, generally reading slightly lower. |
| Miller | A 1983 alternative, reading lower again at greater heights. |
| Hamwi | A 1964 formula developed for diabetes management. |
The inputs explained
| Field | What to enter |
|---|---|
| Height (cm) | Height in centimetres. |
| Sex | Biological sex, which changes both the base weight and the per-inch increment. |
When to use it
Understanding the spread between methods
The four figures typically differ by several kilograms. Rather than choosing one, read the spread as a rough band: and note that the healthy BMI range shown alongside is usually wider still.
Clinical dose calculations
This is what Devine was actually designed for. Some medications are dosed on ideal rather than actual body weight, which is why the formula persists in clinical practice.
Putting a weight goal in context
If a target weight sits far outside every formula and outside the healthy BMI range, that is worth discussing with a doctor. If it sits within the range, the precise number matters much less than habits and health markers do.
Seeing why height matters less than expected
The formulas add only 1.7 to 2.7 kg per inch of height. Weight is far less determined by height than most people assume, and body composition explains far more.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
Ideal weight at different heights
The four formulas compared across a range of heights.
| Height | Devine | Robinson | Miller | Hamwi |
|---|---|---|---|---|
| 160 cm | 56.9 kg | 57.7 kg | 60.4 kg | 56.1 kg |
| 170 cm | 65.9 kg | 65.2 kg | 66.0 kg | 66.7 kg |
| 175 cm | 70.5 kg | 68.9 kg | 68.7 kg | 72.0 kg |
| 180 cm | 75.0 kg | 72.6 kg | 71.5 kg | 77.3 kg |
| 190 cm | 84.0 kg | 80.1 kg | 77.1 kg | 88.0 kg |
| 200 cm | 93.1 kg | 87.6 kg | 82.6 kg | 98.6 kg |
How the healthy BMI range compares
The same comparison for women, with the healthy BMI range alongside.
| Height | Devine | Hamwi | Healthy BMI range |
|---|---|---|---|
| 155 cm | 47.9 kg | 47.8 kg | 44.4 – 59.8 kg |
| 160 cm | 52.4 kg | 52.1 kg | 47.4 – 63.7 kg |
| 165 cm | 56.9 kg | 56.4 kg | 50.4 – 67.8 kg |
| 170 cm | 61.4 kg | 60.7 kg | 53.5 – 72.0 kg |
| 175 cm | 66.0 kg | 65.1 kg | 56.7 – 76.3 kg |
| 180 cm | 70.5 kg | 69.4 kg | 59.9 – 80.7 kg |
Questions
Which ideal weight formula is best?
None is authoritative for personal use. Devine is the clinical standard for medication dosing, which is what it was designed for. For thinking about your own weight, the healthy BMI range is a broader and more appropriate reference.
Why do the formulas disagree?
They were derived from different populations at different times using different methods. The disagreement is a fair reflection of genuine uncertainty about what any single ideal weight would even mean.
Do these account for build or muscle?
No. They use height and sex only. Someone with a heavier frame or substantial muscle may sit well above these figures while being entirely healthy, which is a significant limitation.
Should I aim for my ideal body weight?
Not as a target in itself. These are reference figures, not goals, and health outcomes depend on far more than weight. If you are thinking about changing your weight, a doctor or accredited dietitian can give advice that accounts for your actual situation.
For screening against the healthy range, see BMI. For body composition, use the body fat calculator.