Pediatric dose calculator by weight
Use this hub when you know the medication and need to get from weight-based dosing to an exact child dose quickly. Start here, then open the medication page for the actual calculator, max limits, and bottle-strength details.
If the hard part is converting mg/kg to mL, choosing between bottle strengths, or sorting out brand versus generic names, the medication pages handle those steps directly.
New to weight-based pediatric dosing?
Start with the parent-friendly explainer on why children’s doses are often based on weight, then return here to use the calculator as a math support tool with clinician or pharmacist confirmation.
Clinical disclaimer
How to use this pediatric dosing calculator hub
- Select a medication from the quick start list below.
- Enter the child's weight in the medication calculator.
- Confirm the result against max daily limits and local protocols.
If you have the medicine in hand
Weight chart for the common 400 mg/5 mL suspension, twice a day at standard and high dose.
Compare Augmentin 228, 457, or ES-600 before you convert the dose into mL.
Open the exact ES-600 support page, then continue into the parent Augmentin calculator with 600/5 selected.
Open this for 15 mg/5 mL liquid bursts and common mg/kg steroid plans.
Use this exact support page for 15 mg/5 mL liquid conversion and burst-dose safety checks.
Use this when the bottle says Pepcid but the prescription is written as famotidine.
Convert the common Pepcid suspension concentration, then open the parent calculator with 40/5 selected.
Convert Zofran or ondansetron 0.15 mg/kg plans into liquid or ODT handoffs during vomiting illnesses.
Match mg/kg dosing to capsules, packets, or liquid form without guessing.
Convert 10 mg/5 mL liquid with sedation, divided-dose, and QT-risk checks visible.
Zyrtec label dose by age, with mL for 5 mg/5 mL liquid.
Claritin label dose by age, with mL for 5 mg/5 mL liquid.
Convert 2 mg/5 mL liquid after checking age, sedation, and duplicate cold-product ingredients.
Use this for croup-style single-dose plans and liquid or tablet conversion.
Handle Tamiflu 6 mg/mL conversion, treatment versus prevention, age checks, and vomiting follow-up.
Convert Keflex 125 mg/5 mL or 250 mg/5 mL suspension into mL after confirming the ordered dose.
Use the exact cephalexin landing page that hands off to the Keflex calculator with a strength preset.
Need bottle-strength or brand-name help?
Open this for Zithromax day-1 loading-dose math and 100 mg/5 mL or 200 mg/5 mL liquid conversion.
Convert cefixime 100 mg/5 mL syrup after confirming the once-daily or split-dose plan.
Convert cefuroxime 125 mg/5 mL or 250 mg/5 mL suspension and keep the with-food rule visible.
Open this when TMP-component math, suspension conversion, or UTI and skin-infection dosing is the hard part.
Use this for 0.15 mg/kg math, liquid versus ODT choices, oral rehydration plans, and repeat-dose cautions.
Open omeprazole when the next step is choosing the right form and getting the before-meal timing right.
Jump to a medication
Amoxicillin-clavulanate dosing for common infections.
First-line dosing for otitis and sinusitis when indicated.
Macrolide option for atypical infections.
Cephalosporin alternative for select infections.
Cephalexin dosing for skin and soft tissue use.
Coverage for anaerobes or toxin-mediated disease.
Steroid dosing for asthma and croup protocols.
Common for croup, asthma, and inflammation.
Famotidine dosing for reflux and GI symptoms.
PPI dosing when indicated for reflux or esophagitis.
Antiviral dosing for influenza when indicated.
Antiemetic dosing for nausea or vomiting protocols.
Weight-based dosing basics (mg/kg)
- Confirm the child's most recent weight in kg before calculating any dose.
- Multiply weight by the mg/kg dose range to get the total mg per dose.
- Use the product concentration on the label to convert mg to mL when needed.
- Round to practical volumes while staying within maximum daily limits.
Converting mg/kg to mL (quick method)
After you calculate the total mg per dose, divide by the concentration on the bottle (mg per mL). This gives the volume in mL. Always double-check the concentration because products vary.
Rounding and dosing intervals
- Round to practical volumes or tablet sizes that are easy to measure.
- Use the dosing interval listed on the medication page (for example, every 6 or 8 hours).
- Stay within the maximum daily dose when multiplying by the number of doses.
Safety checks before dosing
- Check for allergies or prior reactions to the medication class.
- Confirm max daily dose and any age or weight cutoffs.
- Review renal and hepatic considerations when applicable.
- Avoid double-dosing with combination products or overlapping therapies.
When to double-check a dose
- Infants and neonates with age-specific dosing limits.
- Obesity or very low weight where standard ranges may not apply.
- Renal impairment or hepatic disease that may require adjustments.
- High-risk medications with narrow safety margins.
Common pediatric medication calculators
- Cefixime pediatric dose calculator
- Cefuroxime pediatric dose calculator
- Cefpodoxime pediatric dose calculator
- Cefprozil pediatric dose calculator
- Cefaclor pediatric dose calculator
- Cefadroxil pediatric dose calculator
- Ceftibuten pediatric dose calculator
- Metronidazole pediatric dose calculator
- Nitrofurantoin pediatric dose calculator
- Bactrim / TMP-SMX pediatric dose calculator
- Fluconazole pediatric dose calculator
- Hydroxyzine dose by weight guide
- Chlorpheniramine dose by weight guide
- Clonidine pediatric dose calculator
Related calculators and workflows
What this hub does and does not do
- Does: Provide fast links to pediatric medication calculators and dosing safety tips.
- Does not: Replace drug labeling, institutional protocols, or clinical judgment.
Frequently asked questions
Calculate the total mg from weight and dose, then divide by the concentration to get mL. Always use the exact concentration on the bottle or label.
Max doses vary by drug and age. Always check the medication-specific calculator or labeling before prescribing.
Round to practical volumes or tablet sizes while staying within safe ranges. Follow institutional rounding policies when available.
Dose adjustments may be required. Use medication-specific notes and consider renal function tools when needed.
Weight-based dosing is more accurate. Use a recent weight whenever possible.
Obtain a weight if possible. Avoid guessing when safety is a concern.