Lean Body Weight Calculator
Lean Body Weight Calculator works out Ideal body weight and Devine from Units, Sex and Height. The default figures on this page give lean body mass of 61.42 kg; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
5 steps
- Height = 180 cm = 70.8661 in, which is 10.8661 in over 5 ft.
- Devine (1974): 50 + 2.3 x 10.8661 = 74.992 kg
- Boer (1984): LBM = 0.407 x 80 + 0.267 x 180 - 19.2 = 61.42 kg
- Implied fat mass = 80 - 61.42 = 18.58 kg
- Healthy weight band for this height (BMI 18.5 to 24.9) = 59.94 to 80.68 kg
Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
10 sources
Keep this result
Save it, change one figure, then compare the two
The calculation stays free. Save this scenario, adjust one assumption, save that too, and put them side by side to see exactly what the change costs you. A free account keeps 5 scenarios and 2 comparisons; Personal makes both unlimited and adds exports and private links. Nothing is saved unless you press Save.
What the Lean Body Weight Calculator calculates
Ideal body weight from the Devine, Robinson, Miller and Hamwi equations, plus the clinical adjusted body weight and lean body mass by the Boer, James, Hume and Janmahasatian equations.
How to use this Lean Body Weight Calculator
Enter Units, Sex, Height and Height (feet). Ideal body weight updates as you type. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Ideal body weight, Devine and Robinson.
The method follows Devine BJ, Gentamicin therapy, Drug Intelligence and Clinical Pharmacy 1974;8:650-655 - IBW(kg) = 50 (men) or 45.5 (women) + 2.3 per inch over 5 ft, Robinson JD et al., Determination of ideal body weight for drug dosage calculations, American Journal of Hospital Pharmacy 1983;40:1016-1019, Miller DR et al., Determining ideal body weight, American Journal of Hospital Pharmacy 1983;40:1622, Hamwi GJ, Therapy: changing dietary concepts, in Diabetes Mellitus: Diagnosis and Treatment, American Diabetes Association 1964 - published in pounds as 106 lb + 6 lb/in (men) and 100 lb + 5 lb/in (women), and carried in the clinical literature as 48.0 + 2.7 kg/in and 45.5 + 2.2 kg/in and Boer P, Estimated lean body mass as an index for normalization of body fluid volumes, American Journal of Physiology 1984;247:F632-636.
What you can compare
Change one input at a time to see how it affects Ideal body weight, Devine and Robinson. The inputs you can vary are Units, Sex, Height, Height (feet), Height (inches) and Actual body weight.
Understanding Ideal body weight, Devine and Robinson
These are population regressions used mainly for drug dosing and nutrition support, not a target to diet towards. Devine in particular was derived for gentamicin dosing, not for health. Adjusted body weight changes drug doses, so a pharmacist or prescriber must confirm any clinical use.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
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Frequently asked questions
What is the ideal weight for my height and age?
On the figures this page opens with — height 177.8 cm and actual body weight 120 — the lean body mass is 61.42 kg. No single number fits everyone: change any figure above and the answer updates as you type, with each step of the arithmetic beside it.
What is the correct height and weight for age?
It needs Units, Sex, Height, Height (feet), Height (inches) and Actual body weight. Nothing else is required, and the figures stay in your browser.
What is the ideal body weight for respiratory therapy?
The result gives Ideal body weight, Devine, Robinson, Miller, Hamwi and Average of the four equations, each labelled with its unit so the figure can be read on its own.
What information do I need for the Lean Body Weight Calculator?
You need Units, Sex, Height, Height (feet), Height (inches), Actual body weight, Extra pounds and Lean body mass equation. The page opens with default figures that give lean body mass of 61.42 kg, so you can see the scale before entering your own.
What does this Lean Body Weight Calculator show?
It shows Ideal body weight, Devine, Robinson, Miller, Hamwi, Average of the four equations, Adjusted body weight and Lean body mass, with the working and any warnings for your entries.
Can I check how the Lean Body Weight Calculator result was calculated?
Yes. The “How this is worked out” section shows the calculation steps, and the sources section identifies the references used for the method.