Pediatric Weight-Based Dose Calculator

Paracetamol 10-15 mg/kg/dose and ibuprofen 5-10 mg/kg/dose are the standard published ranges in the WHO Model Formulary for Children, the BNF for Children (UK), and the American Academy of Pediatrics OTC dosing guidance. We use the midpoint by default; the result card shows the full safe range.

Infants under 6 months have immature kidney function and are vulnerable to dehydration. Ibuprofen reduces renal blood flow and can cause acute kidney injury in this group. Paracetamol is preferred under 6 months (and even paracetamol is doctor-only under 2 months).

Most paediatric drug references recommend weight-based dosing over age-based dosing, because age-based tables assume average-for-age weight. Weight-based dosing is generally more accurate for children at the extremes (small-for-age or overweight). When a recent weight is not available, the lowest of the age-or-weight estimates is a conservative default, and a pharmacist can confirm before the dose is given.

Use the 'Custom drug' option. Enter the mg/kg/dose from the product label (e.g. amoxicillin is typically 20-30 mg/kg/dose three times daily for common infections). For antibiotics, the prescriber's exact instructions are the authoritative reference — they account for the infection type and severity, not just weight.

Yes — round to the nearest 0.5 mL marking on the syringe or cup. Don't round up by more than 10% of the calculated dose. If the calculated mL falls between markings, round DOWN for safety unless the symptoms clearly justify the higher dose.