Ideal Body Weight Calculator

The ideal body weight for overweight or obese adults can be estimated based on the following formula:

Females: 45.5 kg + 0.91 (height - 152.4 cm) or 45.5 kg + 2.3 kg per inch above 5 feet

Males: 50.0 kg + 0.91 (height - 152.4 cm) or 50 kg + 2.3 kg per inch above 5 feet

For example, a man who weighs 90 kg and is 5 feet 5 inches tall, his body weight = 50 + (2.3 × 5) = 61.5 kg

Maintenance fluid = (4 × 10) + (2 × 10) + (1 × 41.5) = 101.5 ml/hour (~2.4 L/day)

Ideal Body Weight Estimation - Children

There is no consensus on the best method to use to calculate the ideal body weight for children.

If the child is overweight or obese (e.g., BMI for age ≥ 85th percentile and ≥ 95th percentile, respectively), use the American growth charts.

Calculate ideal body weight using the BMI method that determines ideal body weight = [BMI at 50th percentile for child's age × (height in meters)2]

For example, ideal body weight for a 4-year-old girl who is 105 cm tall (BMI at 50th percentile for age/sex is 15.3).2

Ideal body weight = 15.3 × 1.05 × 1.05 = 16.9 kg