Clinical Calculator
Ideal Body Weight Calculator (Devine & Robinson Formula)
Determine your ideal body weight (IBW) range online using the established Devine and Robinson clinical equations based on height and gender.
Understanding Ideal Body Weight (IBW)
Ideal Body Weight (IBW) equations were originally developed in clinical settings to calculate clearances for hydrophilic medications (like gentamycin) and guide ventilator settings in critical care. Today, they serve as general reference ranges for healthy weight targets.
Clinical Equations Used
This calculator utilizes two of the most widely accepted clinical formulas, both calibrating weight relative to height over a baseline of 5 feet (60 inches):
- Devine Formula (1974):
- Male: 50.0 kg + 2.3 kg per inch over 5 ft
- Female: 45.5 kg + 2.3 kg per inch over 5 ft
- Robinson Formula (1983):
- Male: 52.0 kg + 1.9 kg per inch over 5 ft
- Female: 49.0 kg + 1.7 kg per inch over 5 ft
These formulas are calibrated for adults over 5 feet tall. For individuals under 5 feet, clinical adjustments or BMI reference curves are typically used instead.
Frequently Asked Questions
The Robinson formula generally estimates a slightly lower ideal weight for women and higher for men compared to the older Devine formula, reflecting minor calibration updates.
No, these classic equations only evaluate height and sex. They do not distinguish between fat mass and skeletal muscle mass, which is a major limitation for athletic individuals.
It is critical for calculating precise medication dosages, particularly for drugs that do not distribute into adipose (fat) tissue, preventing toxicity.