Free Online Tool

Paracetamol Dosage Calculator

Calculate the safe paracetamol dosage based on weight and medicine concentration. Provides dose in mg and ml for infants, children, and adults.

Weight (kg)

Age Group (if weight unknown)

Medicine Concentration

What is the Paracetamol Dosage Calculator?

The Paracetamol Dosage Calculator is a free online tool that helps parents, caregivers, and healthcare workers calculate the safe and effective dose of paracetamol (acetaminophen) based on body weight and medicine concentration. Paracetamol is one of the most commonly used medicines for fever and pain relief in children and adults. However, incorrect dosing — especially in children — can lead to ineffective treatment or, in severe cases, liver toxicity. Our calculator follows standard medical guidelines from the WHO and national formularies, providing a dose range of 10-15 mg per kilogram of body weight per dose, with clear maximum daily limits.

Weight-based dosing is the gold standard for paracetamol because age alone is an unreliable indicator. Two children of the same age can have significantly different weights, and giving the same dose to both could underdose one and overdose the other. This calculator eliminates the guesswork by converting weight and concentration into precise milligram and milliliter doses. Whether you have infant drops (100 mg/ml), pediatric suspension (250 mg/5ml), or adult tablets (500 mg), the calculator adjusts automatically to give you the correct dose for your specific medicine.

How to Use the Paracetamol Dose Calculator

Follow these steps:

Enter Weight: Enter the person\'s weight in kilograms. If you don\'t know the exact weight, select the age group for an approximate weight estimate.
Select Medicine Concentration: Choose the paracetamol formulation you have — infant suspension (120 mg/5ml), pediatric suspension (250 mg/5ml), tablets (500 mg or 650 mg), infant drops (100 mg/ml), or oral solution.
Click Calculate: Instantly see the minimum and maximum single doses in mg, the approximate volume in ml, maximum daily dose, and recommended dosing interval.

The calculator provides a dose range rather than a single dose because 10-15 mg/kg is the standard safe range. For mild fever or pain, use the lower end (10 mg/kg). For high fever or moderate pain, use the higher end (15 mg/kg). Always use the measuring device that comes with the medicine (syringe, cup, or dropper) for accurate measurement.

Understanding Paracetamol Dosing Guidelines

Paracetamol dosing follows internationally accepted guidelines. The standard single dose is 10-15 mg per kg of body weight, administered every 4-6 hours. The maximum daily dose is 60 mg per kg per day (not exceeding 4000 mg for adults). No more than 4-5 doses should be given in 24 hours with at least 4 hours between doses. For infants under 3 months, paracetamol should only be given under medical supervision. For term neonates (under 28 days), the dose is 7.5 mg/kg every 6-8 hours. These guidelines ensure safe and effective treatment while minimizing the risk of adverse effects.

Single Dose = Weight (kg) × 10-15 mg | Maximum Daily = Weight × 60 mg (max 4000 mg)

For example, a child weighing 15 kg: Single dose = 150-225 mg. Maximum daily = 900 mg. At 250 mg/5ml suspension, this is 3-4.5 ml per dose. The maximum daily dose of 900 mg means no more than 18 ml per day (about 4-5 doses of 3.6-4.5 ml each). Always round to a measurable amount using the syringe provided.

Safety Precautions and Warnings

Paracetamol is safe when used as directed, but overdose can cause serious liver damage. Never exceed the recommended dose or dosing frequency. Be aware that many over-the-counter cold and flu medicines contain paracetamol as an ingredient — always check the active ingredients and avoid doubling up. Do not give paracetamol with other paracetamol-containing products. If fever persists for more than 3 days or pain for more than 5 days, consult a doctor. For children, use the child\'s weight for dosing, not the adult dose. Store all medicines out of reach of children. If you suspect an overdose, contact a poison control center or emergency services immediately. The antidote N-acetylcysteine (NAC) is most effective when given within 8 hours of overdose.

Paracetamol vs Other Antipyretics

Paracetamol is often compared to ibuprofen (another common fever and pain reliever). Paracetamol is preferred for patients with stomach ulcers, asthma, or bleeding disorders because it does not irritate the stomach or affect blood clotting. Ibuprofen has anti-inflammatory properties that paracetamol lacks, making it more effective for inflammatory conditions like arthritis, ear infections, and muscle injuries. Paracetamol and ibuprofen can be alternated every 3 hours (with 6 hours between ibuprofen doses and 4 hours between paracetamol doses) under medical guidance for difficult-to-control fevers. However, it is important to keep a written log of all medicines given to avoid accidental double dosing. Our calculator focuses on paracetamol dosing only — always consult a doctor for specific medical advice.

Frequently Asked Questions

How to calculate paracetamol dosage by weight?

The standard paracetamol dosage is 10-15 mg per kilogram of body weight per dose, given every 4-6 hours. The maximum daily dose is 60 mg/kg/day (max 4000 mg for adults). For example, a child weighing 15 kg: 15 × 10 = 150 mg per dose (minimum), 15 × 15 = 225 mg per dose (maximum). With 250 mg/5ml suspension, one dose would be 3-4.5 ml. Our calculator does this automatically based on weight and medicine concentration.

What is the safe paracetamol dosage for adults?

For adults (over 50 kg), the standard paracetamol dosage is 500-1000 mg (one to two 500mg tablets) every 4-6 hours as needed. Do not exceed 4 doses (4000 mg) in 24 hours. The minimum interval between doses is 4 hours. For adults under 50 kg, calculate at 10-15 mg/kg/dose. Extended-release formulations have different dosing (1300 mg every 8 hours, max 3900 mg/day). Always follow the maximum daily limit to avoid liver toxicity.

How to calculate paracetamol dosage for infants?

For infants, paracetamol dosage is strictly weight-based: 10-15 mg/kg every 4-6 hours, maximum 4 doses per day (60 mg/kg/day). Infant drops come in higher concentrations (100 mg/ml or 120 mg/5ml). A 5 kg infant: 5 × 10 = 50 mg per dose minimum, 5 × 15 = 75 mg per dose maximum. With 100 mg/ml drops, this is 0.5-0.75 ml per dose. Always use the syringe provided with the medicine for accurate measurement. Consult a doctor for infants under 3 months.

What is the maximum paracetamol dose in 24 hours?

The maximum daily dose of paracetamol is: Adults (over 50kg) — 4000 mg (4 grams) per 24 hours. Children — 60 mg/kg per day, not exceeding 4000 mg. For example, a 20 kg child: max daily dose = 20 × 60 = 1200 mg per day (≈ 5 doses of 240 mg). Never exceed the maximum daily dose regardless of symptom severity. Severe liver damage can occur with doses above 4000 mg per day in adults or 150 mg/kg in children.

What is the interval between paracetamol doses?

The minimum interval between paracetamol doses is 4 hours. The recommended dosing schedule is every 4-6 hours as needed for fever or pain. Do not give more than 5 doses in 24 hours (for children) or 4 doses (for adults with 1000 mg per dose). Setting a timer or keeping a dosing log is helpful to avoid accidental overdosing, especially when caring for a sick child through the night.

How to convert paracetamol mg to ml?

To convert paracetamol mg to ml, divide the desired dose in mg by the concentration in mg per ml. Common concentrations: 120 mg/5ml (24 mg/ml) — infant suspension; 250 mg/5ml (50 mg/ml) — pediatric suspension; 500 mg tablet; 100 mg/ml — infant drops. Example: for a 150 mg dose with 250 mg/5ml suspension: 150 ÷ 50 = 3 ml. Our calculator handles all standard concentrations automatically.

What happens if I take too much paracetamol?

Paracetamol overdose is dangerous and can cause severe liver damage. The toxic dose is typically above 150 mg/kg or 7-10 grams in adults. Symptoms in first 24 hours include nausea, vomiting, abdominal pain, and pallor. After 24-48 hours, liver damage develops with elevated liver enzymes. Severe overdose can cause liver failure, requiring transplantation, and can be fatal. If overdose is suspected, seek emergency medical attention immediately. Activated charcoal within 1-2 hours and N-acetylcysteine (NAC) are effective antidotes.

Can I give paracetamol to a 2-month-old baby?

Paracetamol can be given to infants from 2 months of age for fever and pain (after vaccination or teething). The dose is 10-15 mg/kg every 4-6 hours. For a 4.5 kg 2-month-old: 45-67.5 mg per dose. Use infant paracetamol drops (100 mg/ml) and measure with the syringe. Maximum 4 doses per day. However, always consult a pediatrician before giving any medicine to infants under 3 months. For babies under 2 months, paracetamol should only be given under medical supervision.

What is the difference between paracetamol and ibuprofen?

Paracetamol (acetaminophen) and ibuprofen are both pain and fever reducers but work differently. Paracetamol is primarily a centrally acting analgesic and antipyretic with minimal anti-inflammatory effect. Ibuprofen is an NSAID with anti-inflammatory, analgesic, and antipyretic effects. Paracetamol can be given every 4-6 hours (max 4-5 doses/day), ibuprofen every 6-8 hours (max 3 doses/day). Paracetamol is safer for the stomach but can cause liver damage in overdose. Ibuprofen can cause stomach ulcers and kidney issues. They can be alternated (every 3 hours) under medical advice.

How to calculate paracetamol dosage for 250mg/5ml suspension?

250 mg/5ml suspension means each 5ml contains 250 mg of paracetamol. Concentration = 50 mg/ml. For a weight-based dose: e.g., child weighing 18 kg. Dose range: 18 × 10 = 180 mg to 18 × 15 = 270 mg. In ml: 180 ÷ 50 = 3.6 ml (minimum) to 270 ÷ 50 = 5.4 ml (maximum). Round to the nearest 0.5 ml on the syringe. Our calculator does this calculation instantly — just enter the weight and select 250 mg/5ml concentration.

Can I take paracetamol on an empty stomach?

Yes, paracetamol can be taken on an empty stomach. Unlike ibuprofen and other NSAIDs, paracetamol does not irritate the stomach lining and does not require food for protection. However, taking it with food may help if you experience mild nausea. The absorption of paracetamol is slightly faster on an empty stomach, so it may work a few minutes quicker. For children who dislike the taste, mixing the suspension with a small amount of milk or juice is acceptable.

How long does paracetamol take to work?

Paracetamol typically starts working within 30-60 minutes after oral administration. Peak effect is reached in 1-2 hours. For faster relief, take on an empty stomach. The duration of action is 4-6 hours. Intravenous paracetamol works faster, within 5-10 minutes. Suppositories take 45-90 minutes to work. If fever or pain persists after the dose, wait at least 4 hours before giving another dose. If there is no improvement after 2-3 days, consult a doctor.

What is paracetamol 500mg used for?

Paracetamol 500mg tablets are used for the relief of mild to moderate pain including headache, toothache, menstrual cramps, muscle aches, backache, osteoarthritis pain, and cold/flu symptoms. It is also used to reduce fever. The adult dose is 500-1000 mg (1-2 tablets) every 4-6 hours, maximum 4000 mg (8 tablets) per day. Do not take with other paracetamol-containing medicines (many cold and flu remedies contain paracetamol). Always check labels to avoid exceeding the maximum daily dose.

How to calculate IV paracetamol dosage?

IV paracetamol dosage: Adults and adolescents over 50 kg — 1000 mg every 6 hours (max 4000 mg/day). Children 10-50 kg — 15 mg/kg every 6 hours (max 60 mg/kg/day). Infants 3-12 months (5-10 kg) — 10 mg/kg every 6 hours. Neonates under 3 months — 7.5 mg/kg every 6-8 hours (max 30 mg/kg/day). IV paracetamol is infused over 15 minutes. Note that IV doses are slightly lower than oral doses due to 100% bioavailability (oral paracetamol has 70-90% bioavailability).