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Body Weight Average Calculator

Body weight average calculator works out Ideal body weight and Devine from Units, Sex and Height. The default figures on this page give average of the four equations of 65.95 kg; change any entry and the result, the working and the sources update together.

Average of the four equations
65.95 kg
Ideal Body Weight Calculator
Ideal body weight
65.94 kg
Ideal body weight
145.4 lb
Devine
65.94 kg
Robinson
65.17 kg
Miller
65.97 kg
Hamwi
66.71 kg
Healthy weight range, lower (BMI 18.5)
53.46 kg
Healthy weight range, upper (BMI 24.9)
71.96 kg
Equation used
Mean of Devine, Robinson, Miller and Hamwi
Height used
170.0 cm
Worked out from 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 and 9 other sources.
The four ideal-weight equations disagree by several kilograms at the same height because they were derived for different purposes; treat any single number as one opinion, not a target.
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.

Your figures

Updates as you type
Metric uses kilograms and centimetres; US uses pounds with feet and inches; UK uses stones and pounds.
Every equation here has separate coefficients for men and women.
Used when the unit system is metric.
Used when the unit system is US or UK.
The inches part of a feet-and-inches height.
Required for adjusted body weight and lean body mass; optional for ideal body weight.
Only used with UK stones-and-pounds: the pounds part, e.g. 11 st 4 lb is weight 11 and extra pounds 4.

How this is worked out

4 steps
  1. Height = 170 cm = 66.9291 in, which is 6.9291 in over 5 ft.
  2. Devine (1974): 50 + 2.3 x 6.9291 = 65.937 kg
  3. Average of the four equations = (65.94 + 65.17 + 65.97 + 66.71) / 4 = 65.945 kg
  4. Healthy weight band for this height (BMI 18.5 to 24.9) = 53.47 to 71.96 kg

Its 5 worked examples are re-run on every release, last on 15 September 2026. What changed

Sources and references

10 sources
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
1974
Robinson JD et al., Determination of ideal body weight for drug dosage calculations, American Journal of Hospital Pharmacy 1983;40:1016-1019
1983
Miller DR et al., Determining ideal body weight, American Journal of Hospital Pharmacy 1983;40:1622
1983
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
1964
Boer P, Estimated lean body mass as an index for normalization of body fluid volumes, American Journal of Physiology 1984;247:F632-636
1984
James WPT, Research on Obesity, HMSO 1976 - the James lean body mass equations
1976
Hume R, Prediction of lean body mass from height and weight, Journal of Clinical Pathology 1966;19:389-391
1966
Adjusted body weight, ABW = IBW + correction x (actual weight - IBW), with a correction factor of 0.4 - the standard obesity dosing adjustment described in Pai MP & Paloucek FP, The origin of the "ideal" body weight equations, Annals of Pharmacotherapy 2000;34:1066-1069
2000

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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.

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What the body weight average 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 body weight average 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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Copy this code into any page. The calculator appears with the figures currently entered, sizes itself to fit, and a small credit line links back here. Free, no account, no ads inside it, no tracking of your readers. Set your own figures and fixed fields; Personal removes the credit line, sets your colour and shows you which sites use it.

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Frequently asked questions

How to calculate average body weight?

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. Open “How this is worked out” beside the result to see each step for your own figures.

What is my average body weight?

On the figures this page opens with — height (inches) 10 — the average of the four equations is 65.95 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 information do I need for the body weight average calculator?

You need Units, Sex, Height, Height (feet), Height (inches), Actual body weight and Extra pounds. The page opens with default figures that give average of the four equations of 65.95 kg, so you can see the scale before entering your own.

What does this body weight average 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 body weight average 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.

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