Paracetamol Dosage Calculator

Weight-Based Paracetamol Dosing for Children

The pediatric paracetamol dose is calculated using body weight as the primary variable. For children over 3 months of age, the standard single dose is 15 mg per kilogram of body weight, which can be given every 4–6 hours as needed. This frequency allows for up to 4 doses within a 24-hour period.

The maximum daily dose for children is 60 mg/kg per day. This ceiling prevents overdose while maintaining therapeutic benefit. Both oral liquid and rectal formulations share identical dosing guidelines—rectal administration does not require dose adjustment, despite sometimes being perceived as less effective.

Liquid formulations are standard for pediatric use because young children struggle to swallow tablets. Always check the concentration listed on the bottle, which may vary (common strengths include 120 mg/5 mL or 250 mg/5 mL). Precise dosing matters especially with infants and toddlers, where small errors can have meaningful consequences.

Paracetamol Dosage Calculation

Use the following formulas to determine safe doses based on the child's weight in kilograms:

• Child's weight — Weight in kilograms; the foundation of all pediatric dose calculations
• Single dose multiplier — 15 mg/kg is the standard pediatric paracetamol dose per administration
• Maximum daily multiplier — Multiply the single dose by 4 to account for the maximum 4 doses in 24 hours

Converting Calculated Doses to Liquid Formulations

Once you have the dose in milligrams, converting to milliliters depends on the syrup concentration. Pediatric paracetamol syrups come in different strengths, so this step is essential to avoid measurement errors.

If your syrup is labeled 120 mg/5 mL, use this formula:

Volume (mL) = (5 × dose in mg) ÷ 120

For a stronger formulation such as 250 mg/5 mL, the equation becomes:

Volume (mL) = (5 × dose in mg) ÷ 250

Always measure liquid doses with a syringe or dropper marked in milliliters rather than a household spoon, which introduces significant dosing variability. Read the concentration on every bottle before calculating, as different manufacturers may supply different strengths.

Key Dosing Considerations and Safety Reminders

Proper paracetamol administration requires attention to several important details.

1. Never exceed 4 doses in 24 hours — Even if a child appears to need more relief, additional doses exceed the maximum daily threshold and risk liver toxicity. Space doses at least 4–6 hours apart. If pain or fever persists despite correct dosing, consult a healthcare provider rather than increasing frequency.
2. Account for paracetamol in combination products — Many cough, cold, and flu remedies for children contain paracetamol. Check all medications your child is taking to avoid hidden paracetamol from multiple sources, which can lead to accidental overdose and serious harm.
3. Verify syrup concentration before measuring — Liquid formulations vary widely in strength. A miscalculation between a 120 mg/5 mL and 250 mg/5 mL product can result in a dose that is either ineffective or dangerously high. Always read the label and use the correct conversion equation.
4. Use age and weight together for very young children — While this calculator uses weight, cross-check results against age-appropriate guidelines for infants and very small toddlers. Developmental factors and liver maturity influence drug metabolism, especially in children under 12 months old.

Comparative Dosing Across Age Groups

Paracetamol dosing differs significantly between children and adults. An adult's single dose is up to 1 g (1,000 mg) per dose, with a daily maximum of 4 g. For chronic use in adults, the daily limit drops to 2.5 g to reduce liver stress.

In children, per-dose limits are much lower: a maximum of 20 mg/kg per single dose, and up to 65 mg/kg per day (though the 60 mg/kg standard is more commonly cited). These differences reflect children's smaller body size and developing organ systems. Always use the child-specific formulas rather than adapting adult dosing by weight alone, as pediatric guidelines include additional safety margins.