Adjusted Body Weight Calculator

This calculator works out your adjusted body weight, a figure that sits partway between ideal body weight and actual weight and is used when someone weighs noticeably more than their ideal weight. Enter your height, your actual weight and your sex, and the calculator first estimates ideal body weight from your height using the widely used Devine formula, then adds back 40 percent of the amount by which your actual weight exceeds that ideal. The result narrows the gap between the two figures, which is why adjusted body weight is preferred over raw actual weight for some body-size estimates in clinical nutrition and related fields, where using full body weight can overstate a figure and ideal weight can understate it. The tool shows the adjusted body weight, the ideal body weight it started from, your actual weight, and the excess over ideal, so you can see exactly how the adjustment is built up. If your actual weight is at or below your ideal weight, the adjustment is not applied and your actual weight is used instead, since the correction only makes sense above ideal weight. This is a general estimate for information only and not medical or dosing advice, so always defer to a doctor, dietitian or pharmacist for clinical decisions.

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cm
kg
83.9 kg
adjusted body weight
Ideal body weight73.2 kg
Actual weight100.0 kg
Excess over ideal26.8 kg

Ideal body weight uses the Devine formula. Adjusted weight adds 40 percent of the excess over ideal weight.

General estimate for information only, not medical or dosing advice. Speak to a doctor, dietitian or pharmacist for clinical decisions.

How it works

Ideal body weight comes from the Devine formula, which starts from a base weight for a height of 5 feet (about 152 cm) and adds 2.3 kg for every inch above that. The base is 50 kg for men and 45.5 kg for women. Your height in centimetres is converted to inches by dividing by 2.54. Adjusted body weight then takes that ideal weight and adds 40 percent of the difference between your actual weight and your ideal weight: adjusted equals ideal plus 0.4 times (actual minus ideal). The 40 percent figure reflects that excess weight is a mix of lean tissue and fat, so only part of it is counted. When actual weight is at or below ideal weight the difference is zero or negative, so the calculator simply returns your actual weight.

Worked example

Take a man who is 178 cm tall and weighs 100 kg. Converting 178 cm to inches gives about 70.08 inches, which is 10.08 inches above 5 feet. Ideal body weight is 50 plus 2.3 times 10.08, which is about 73.2 kg. His excess over ideal is 100 minus 73.2, which is 26.8 kg. Adjusted body weight is 73.2 plus 0.4 times 26.8, so 73.2 plus 10.7, which comes to about 83.9 kg. That adjusted figure sits between his ideal 73.2 kg and his actual 100 kg, exactly as intended.

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Frequently asked questions

What is adjusted body weight?

Adjusted body weight is an estimate that sits between your ideal body weight and your actual weight. It is used when someone weighs well above their ideal weight, because using full actual weight can overstate certain body-size estimates while ideal weight understates them. The standard formula adds 40 percent of the excess over ideal weight back onto the ideal weight.

How do you calculate adjusted body weight?

First find ideal body weight from height and sex using the Devine formula. Then take adjusted body weight equals ideal body weight plus 0.4 times (actual weight minus ideal body weight). For a man of 178 cm weighing 100 kg, ideal weight is about 73.2 kg, so adjusted weight is 73.2 plus 0.4 times 26.8, which is about 83.9 kg.

When is actual weight used instead?

When someone is at or below their ideal body weight the adjustment is not applied, and their actual weight is used. Adjusted body weight is only meaningful when actual weight is above ideal weight, which is when the 40 percent correction narrows the gap between the two figures.