Ideal Weight Calculator
Ideal body weight by Devine, Robinson, Miller and Hamwi. Runs in your browser.
About this ideal weight calculator
This ideal weight calculator shows what the main ideal body weight formulas give for your height and sex, next to the healthy BMI range. It is for adults who want a sensible target, and for students and clinicians who need a quick Devine or Robinson figure.
You get five formulas side by side: Robinson, Miller, Devine, Hamwi and the newer Peterson equation. A chart puts them on one line with the healthy BMI band shaded, and you can add your current weight to see where you stand.
No single number is your 'ideal'. The formulas disagree by several kilos, which is the most honest thing they can tell you, so the page shows the spread instead of one magic figure.
Features
Five formulas at once
Robinson (1983), Miller (1983), Devine (1974), Hamwi (1964) and Peterson (2016), each with its equation, in kg and lb.
Healthy BMI range
The weight that gives a BMI of 18.5 to 24.9 at your height, or 18.5 to 22.9 if you choose the Asian cut-offs.
Frame size
Hamwi's rule of about 10% less for a small frame and 10% more for a large one, applied to the four classic formulas.
Chart with your weight
Every result as a dot on one scale, the BMI band shaded, and a red line at your current weight if you enter it.
Metric or imperial
Centimetres or feet and inches. Switching converts your height instead of clearing it.
Short-height warning
Below 5 ft the classic formulas are stretched past what they were written for, and the page tells you so.
How to use the ideal weight calculator
- 1Pick units and sex, then enter your height.
- 2Optionally set your frame size, BMI cut-offs and current weight.
- 3Compare each formula with the healthy BMI range on the table and chart.
When to use it
Setting a weight goal
Pick a target inside the BMI band, then turn that goal into a daily calorie target with a date.
Drug dosing and nursing
Some medicines are dosed on ideal or adjusted body weight. The Devine figure is the one most often used, and the table shows it in kg.
Checking an old chart
If a doctor or a height-weight chart gave you a number years ago, see which formula it probably came from.
How is ideal body weight calculated?
The four classic formulas all start from a base weight at 5 feet (152.4 cm) and add a fixed amount for every inch above that. They differ only in those two numbers.
Worked example for a man 5 ft 10 in (177.8 cm), which is 10 inches over 5 ft. Devine gives 50 + 2.3 × 10 = 73 kg. Robinson gives 52 + 1.9 × 10 = 71 kg. Miller gives 56.2 + 1.41 × 10 = 70.3 kg. Hamwi gives 48 + 2.7 × 10 = 75 kg. The healthy BMI range at that height is about 58.5 to 78.7 kg.
Peterson's 2016 equation works differently. It aims at a target BMI (22 by default) and is written to work at any height: 2.2 × BMI + 3.5 × BMI × (height in metres − 1.5).
- Robinson (1983): men 52 kg + 1.9 kg per inch, women 49 kg + 1.7 kg per inch
- Miller (1983): men 56.2 kg + 1.41 kg per inch, women 53.1 kg + 1.36 kg per inch
- Devine (1974): men 50 kg + 2.3 kg per inch, women 45.5 kg + 2.3 kg per inch
- Hamwi (1964): men 48 kg + 2.7 kg per inch, women 45.5 kg + 2.2 kg per inch
Which ideal weight formula should I use?
For a personal goal, use the healthy BMI range. It is backed by large population studies on health risk, while the formulas were mostly made for working out medicine doses. Devine is the one hospitals still use most for dosing, Robinson and Miller were later attempts to fit height-weight tables better, and Hamwi was a quick bedside rule.
If the formulas cluster near the middle of your BMI range, any of them is a fair target. If you are muscular, all of them will look low; your body fat percentage is a better guide.
Why do the formulas disagree so much?
Each one was fitted to a different group of people, with different heights and builds, decades apart. They also grow at different rates per inch, so the gap widens for very tall or very short people. At 6 ft 4 in, Hamwi and Miller can be more than 10 kg apart for a man.
Why use Mavros
| Mavros | Typical upload sites | |
|---|---|---|
| Formulas | Robinson, Miller, Devine, Hamwi and Peterson | Four classic formulas |
| Frame size | Small, medium or large adjustment | Mentioned in text only |
| Chart | All results and your weight on one scale | Table only |
| Asian BMI cut-offs | Optional 18.5 to 22.9 range | WHO range only |
| Privacy | Runs in your browser | Inputs sent to a server |
Tips
- Measure your height barefoot against a wall. Half an inch changes most results by about 1 kg.
- If you know your height only in feet and inches, enter it directly or convert it to centimetres.
- Treat the formulas as a range, not a rule. Most adults are healthy anywhere inside the BMI band.
- For a quick health read that also gives calories and BMR, use the BMI calculator.
Questions
What is my ideal weight for my height?
For most adults, any weight that gives a BMI of 18.5 to 24.9 is healthy. At 170 cm that is about 53.5 to 72 kg. The formulas on this page give single figures that usually land in the middle of that range.
What is the Devine formula?
Devine (1974) gives ideal body weight as 50 kg plus 2.3 kg per inch over 5 ft for men, and 45.5 kg plus 2.3 kg per inch for women. It was written for drug dosing and is still widely used in hospitals.
Is ideal body weight the same as healthy weight?
No. Ideal body weight is one formula's single number. Healthy weight is a range linked to lower health risk, usually the BMI 18.5 to 24.9 band.
Do the formulas work if I'm under 5 feet tall?
Not well. They were written for people 5 ft (152.4 cm) and taller. Below that, the calculator extends them downward and shows a warning. Use the Peterson figure and the BMI range instead.
How do I know my frame size?
A common check is your wrist: if your thumb and middle finger overlap around it, you likely have a small frame; if they just touch, medium; if they don't meet, large. Choose 'medium' if unsure.
Does age change my ideal weight?
The formulas ignore age. Muscle tends to drop with age, so the same weight can mean more fat later in life. That is one reason to also track waist size or body fat.
Why does the formula say I'm overweight when I'm fit?
The formulas only know height and sex. Muscle is heavy, so lean, muscular people often weigh more than every formula suggests and are still healthy.
Is this medical advice?
No. These are general estimates for adults. Talk to a doctor or dietitian before setting a weight target, especially if you are pregnant, under 18, or managing a health condition.