Ideal Body Weight Calculator

What is Ideal Body Weight?

Ideal Body Weight (IBW) is an estimated weight range considered healthy for an individual based on their height and gender. It's used as a general guideline in medical and fitness contexts to assess whether a person is at a weight that minimizes health risks.

The Robinson Formula for Ideal Body Weight Calculation

The Robinson formula is one of several methods used to estimate ideal body weight:

For males: \(IBW = 52 \text{ kg} + 1.9 \text{ kg} \times (\text{height in inches} - 60)\)

For females: \(IBW = 49 \text{ kg} + 1.7 \text{ kg} \times (\text{height in inches} - 60)\)

Where:

• \(IBW\) = Ideal Body Weight in kilograms
• \(\text{height in inches}\) = Individual's height converted to inches

Step-by-Step IBW Calculation

1. Convert height to inches if necessary: \[\text{Height in inches} = \text{Height in cm} \div 2.54\]
2. Apply the Robinson formula based on gender:
   • For males: \(IBW = 52 + 1.9 \times (\text{height in inches} - 60)\)
   • For females: \(IBW = 49 + 1.7 \times (\text{height in inches} - 60)\)
3. Calculate the result to get the ideal body weight in kilograms.

Example Calculation

Let's calculate the ideal body weight for a male who is 180 cm tall:

1. \(\text{Height in inches} = 180 \text{ cm} \div 2.54 = 70.87 \text{ inches}\)
2. \(IBW = 52 + 1.9 \times (70.87 - 60)\)
3. \(IBW = 52 + 1.9 \times 10.87 = 72.65 \text{ kg}\)

Visual Representation

The green portion of the bar represents the calculated IBW (72.65 kg) relative to 150 kg.