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).

Always weight, not age. Dose-by-age tables are a rough approximation that assumes average-for-age weight. Weight-based dosing is more accurate, especially for children at the extremes (small-for-age or overweight). If you don't have a recent weight, use the lowest of the age-or-weight estimates and ask your pharmacist.

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). Always defer to the prescriber's exact instructions for antibiotics — 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.