This calculator is a hobby project for educational purposes only. Always consult a qualified medical practitioner before administering any medication to a child.
The formulas used are based on published methods but may not be suitable for all situations.
Used for children 2-12 years:
Used for children under 1 year:
Used for children 1-2 years:
Different methods are appropriate for different scenarios:
- Young's Rule: Best for children aged 2-12 years
- Clark's Rule: More accurate when weight is available
- Fried's Rule: Specifically designed for infants under 1 year
- Cowling's Rule: Alternative age-based method
- BSA Method: Most accurate method, requires height and weight
- Weight Based: Used when medication has established mg/kg dosing
- Dilling's Rule: Designed for toddlers 1-2 years old
- Augsberger's Rule: Alternative age-based method for all pediatric ages
Each method uses different physiological parameters to estimate appropriate dosing. The BSA method is generally considered the most accurate as it accounts for metabolic rate, which correlates better with body surface area than with age or weight alone.
No. These formulas provide estimates only. Many factors affect how a child responds to medication including organ maturity, genetics, and specific medical conditions. Always consult a healthcare provider.
Weight-based (mg/kg) dosing is often used for medications that have established pediatric doses based on weight. The other methods calculate a fraction of the adult dose based on the child's age, weight, or body surface area.
No. Some medications have specific pediatric formulations and dosing guidelines that don't follow these standard formulas. Some medications are not appropriate for children at all.
Body Surface Area (BSA) is the measured or calculated surface area of the human body. It's often used in medicine to calculate doses because it correlates better with many physiological parameters than body weight.
Weight-based formulas are generally more accurate than age-based formulas because weight correlates better with metabolism than age. If a child's weight is available, it's preferable to use a weight-based method. The BSA method (using both height and weight) is considered the most accurate of all.