1. What is BMI and IBW?

Body Mass Index (BMI) is a measure of body fat based on height and weight. Ideal Body Weight (IBW) is an estimate of what your weight should be based on your height, gender, and frame size.

2. How Does the Calculator Work?

The calculator uses the following formulas:

Frame size is determined by the ratio of height to wrist circumference:

• Men: Small (r > 10.4), Medium (9.6-10.4), Large (r < 9.6)
• Women: Small (r > 11.0), Medium (10.1-11.0), Large (r < 10.1)

3. Importance of Frame Size Adjustment

Details: Frame size accounts for differences in body composition. People with larger frames can carry more weight naturally, while those with smaller frames should aim for the lower end of their IBW range.

4. Using the Calculator

Tips: Measure wrist circumference at the smallest part of your wrist. Enter height in inches, weight in pounds, and wrist circumference in inches. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a healthy BMI range?
A: 18.5-24.9 is considered normal weight, 25-29.9 overweight, and 30+ obese.

Q2: Why is IBW given as a range?
A: The ±10% accounts for natural variations in body composition and frame size.

Q3: How accurate is wrist measurement for frame size?
A: It's a simple screening tool. For precise body composition analysis, more advanced methods are needed.

Q4: Should athletes use this calculator?
A: Athletes with high muscle mass may have misleading BMI results. Body fat percentage may be more useful.

Q5: How often should I check my BMI and IBW?
A: For most adults, checking every 3-6 months is sufficient unless actively trying to change weight.