The healthy range first
The lowest and highest weight of a normal BMI for your height, with the gap to your current weight.
Health & wellness
Ideal weight calculator
Healthy weight range for a BMI of 18.5 to 24.9 at your height, compared with the clinical and European ideal body weight formulas.
Height and profile
The result appears as soon as you enter your height. The other fields add formulas or the gap with your current weight.
Sex used by the formulas
Height
Your current weight is only used to show the gap with the healthy BMI range.
Adds the Creff formula, which takes age into account.
Measured just above the wrist bone; adds the Monnerot-Dumaine formula.
Your reference weight
Healthy weight range (BMI 18.5 to 24.9)
This is the World Health Organization reference for an adult of your height. It does not account for muscle mass or build.
By ideal weight formula
- Devine1974, the most used in medicine to dose some drugs
- -
- Robinson1983, a revision of Devine
- -
- Miller1983, higher values for shorter heights
- -
- Hamwi1964, in pounds per inch
- -
- Broca1871, height in cm minus 100
- -
- Lorentz1929, the most common formula in France
- -
- Crefftakes age into account, average build
- -
- Monnerot-Dumainetakes bone frame into account through the wrist
- -
Enter your age to add Creff and your wrist circumference to add Monnerot-Dumaine.
Method & sources
The tool first works out the weight range matching a BMI of 18.5 to 24.9, the WHO reference. It then compares it with the so-called ideal body weight formulas: four clinical equations that start from a base weight at 5 ft and add a weight per inch, and four European formulas based on height in centimetres.
Formula
Healthy range: 18.5 × height² to 24.9 × height² (height in metres) · Devine: 50 kg (men) or 45.5 kg (women) + 2.3 kg per inch over 5 ft · Hamwi: 106 lb (men) or 100 lb (women) + 6 or 5 lb per inch over 5 ftLimitations
- Ideal weight formulas give different results for the same height; none of them sets a personal target.
- They do not account for muscle mass, fat distribution or health status.
- Below 5 ft, the clinical equations are extrapolated and their values become unreliable.
Sources
- Review of historical ideal body weight formulas
- Peterson et al. (2016) - a new body weight equation and formula comparison
- Broca (1871), Lorentz (1929), Creff and Monnerot-Dumaine formulas - French clinical use
Was this tool useful?
How does this tool work?
There is no single ideal weight: every formula gives a different figure. This calculator first shows the healthy weight range for your height according to BMI, then compares it with the best-known formulas, from Devine and Hamwi to the Lorentz and Creff formulas used in France.
Choose the sex used by the formulas and enter your height in feet and inches or centimetres: the healthy range and the formulas appear straight away. Your current weight, optional, adds the gap with the range; age adds the Creff formula and wrist circumference the Monnerot-Dumaine formula.
The healthy range multiplies the square of your height by 18.5 and 24.9. The ideal weight formulas each follow their own calculation; the gap between the lowest and the highest shows how much an "ideal" weight depends on the method.
How to use this tool
Enter your height
In feet and inches or centimetres, then choose the sex used by the formulas.
Add more if you wish
Your current weight for the gap with the healthy range, your age for Creff and your wrist for Monnerot-Dumaine.
Read the healthy range first
It is the reference; the formulas then show how varied the estimates are.
Good to know
Eight formulas compared
Devine, Robinson, Miller and Hamwi alongside Lorentz, Broca, Creff and Monnerot-Dumaine.
Every unit
Feet and pounds, stones or centimetres and kilograms: the result updates as you type.
Ideal weight formulas
The BMI range is the reference; ideal weight formulas each give a single estimate.
Healthy range (BMI)
18.5 × height² to 24.9 × height² (height in metres)
Devine
Men: 50 kg + 2.3 kg per inch over 5 ft · Women: 45.5 kg + 2.3 kg per inch
Hamwi
Men: 106 lb + 6 lb per inch over 5 ft · Women: 100 lb + 5 lb per inch
Robinson
Men: 52 kg + 1.9 kg per inch over 5 ft · Women: 49 kg + 1.7 kg per inch
Lorentz
Men: height − 100 − (height − 150) ÷ 4 · Women: height − 100 − (height − 150) ÷ 2.5 (height in cm)
- height
- Height in centimetres (in metres for the BMI range)
- inch over 5 ft
- Each inch of height above 60 inches
These formulas give orders of magnitude; they do not replace advice from a health professional.
Use cases
Know the healthy weight range for your height
Get the lowest and highest weight of a normal BMI, and the gap with your current weight.
Compare ideal weight formulas
See Devine, Robinson, Miller, Hamwi, Lorentz, Broca, Creff and Monnerot-Dumaine side by side.
Find a clinical reference value
The Devine formula is still used to calculate some drug doses and ventilator settings.
Tips and best practices
- Keep the healthy range in mind rather than a single figure: a stable weight within it is generally linked with the lowest risk.
- Measure your wrist with a soft tape, just above the wrist bone, without pulling tight.
- If you are very muscular, height-based formulas overstate the gap; waist size and waist-to-hip ratio say more about fat distribution.
Frequently asked questions
How do I calculate my ideal weight?
The most recognised method is the weight range matching a BMI of 18.5 to 24.9: multiply the square of your height in metres by those two values. For 5 ft 7 in (1.70 m), that is about 118 to 159 lb (53.5 to 72 kg). Formulas such as Devine or Hamwi then give a single figure inside or near that range.
What is the Devine formula?
Ideal weight = 50 kg for men or 45.5 kg for women, plus 2.3 kg per inch over 5 ft. For a man of 5 ft 10 in: 50 + 2.3 × 10 = 73 kg (161 lb). Created in 1974 to dose drugs, it is still the most used in hospitals.
What is the difference between Devine, Robinson, Miller and Hamwi?
All four start from a base weight at 5 ft and add a weight per inch, but with different values. Hamwi (1964) is in pounds, Devine (1974) is the clinical standard, Robinson and Miller (1983) are revisions: Miller gives higher values for short people and lower ones for tall people.
Why do the formulas give different results?
They were built at different times, from different populations and for different, often medical, purposes. A gap of 10 to 20 lb between the lowest and highest is common and shows there is no single ideal weight.
What are the Lorentz, Creff and Monnerot-Dumaine formulas?
They are formulas used in France. Lorentz depends on height and sex; Creff adds age; Monnerot-Dumaine adds bone frame through wrist circumference. Enter the optional fields to include them.
Do these formulas work for people under 5 ft?
Devine, Robinson, Miller and Hamwi start at 5 ft. Below that, the tool extends them but warns that they become unreliable; the BMI range and the Lorentz formula are then better references.
Can I use this calculator for a child or during pregnancy?
No. These figures are designed for adults. Growth and pregnancy require dedicated charts and follow-up.
Related tools
Keep going with these tools
Tools similar or complementary to this one.
Similar tools
Calculate your body mass index from height and weight, with adult reference ranges and clearly explained limitations.
Health & wellnessNewFeaturedUse this tool
Calculate body surface area in m² from height and weight, with the Mosteller, Du Bois, Haycock, Gehan-George and Boyd formulas.
Health & wellnessNewUse this tool
Work out your bra size from your underbust and bust measurements, with UK, US, EU, French, Italian and Australian sizes and sister sizes.
Health & wellnessNewFeaturedUse this tool
Read next
GuideBest practicesBeginner
Zakat and Nisab: understanding the 2.5% calculation
Learn how the Nisab threshold, gold and silver standards, net eligible assets and the 2.5% rate fit together - and where a Zakat calculator's assumptions matter.
17 September 20263 min