Dosage Calculation Practice
Unlimited randomized nursing math problems with step-by-step solutions
Step-by-Step Solution (Dimensional Analysis)
📖 Quick Formula Reference
Desired Over Have
(Desired dose ÷ Available dose) × Quantity = Amount to give
Order: 500 mg. Available: 250 mg/tablet → (500 ÷ 250) × 1 = 2 tablets
IV Flow Rate (mL/hr)
Total volume (mL) ÷ Time (hours) = mL/hr
1000 mL over 8 hr → 1000 ÷ 8 = 125 mL/hr
IV Drip Rate (gtt/min)
(Volume (mL) × Drop factor (gtt/mL)) ÷ Time (min) = gtt/min
500 mL, 15 gtt/mL, 4 hr → (500 × 15) ÷ 240 = 31 gtt/min
Weight-Based Dosing
Patient weight (kg) × Dose per kg = Total dose
70 kg × 2 mg/kg = 140 mg
Pounds to Kilograms
Weight (lb) ÷ 2.2 = Weight (kg)
154 lb ÷ 2.2 = 70 kg
Reconstitution
Dose ordered ÷ Concentration after mixing = Volume to administer
500 mg ordered, reconstituted to 250 mg/mL → 500 ÷ 250 = 2 mL
About This Dosage Calculation Practice Tool
This free interactive tool generates unlimited randomized nursing math practice problems with step-by-step solutions using dimensional analysis. Every problem uses clinically realistic medication names, doses, and concentrations that you would encounter in nursing school and on the NCLEX exam.
Problem Types
- Oral & Tablet Dosage — Calculate the number of tablets or volume of liquid medication to administer based on the provider's order and the available supply.
- Weight-Based Dosing — Convert patient weight from pounds to kilograms and calculate doses ordered in mg/kg, mcg/kg, or units/kg.
- IV Flow Rate (mL/hr) — Determine the pump rate in mL/hr for continuous IV infusions based on the total volume and infusion time.
- IV Drip Rate (gtt/min) — Calculate drops per minute using the volume, time, and tubing drop factor (10, 15, 20, or 60 gtt/mL).
- Unit Conversions — Convert between mg and mcg, g and mg, mL and L, pounds and kg, and other common nursing conversions.
- Reconstitution — Calculate the volume to administer after mixing a powdered medication with diluent to a specified concentration.
- Safe Dose Range — Determine whether a prescribed dose falls within the recommended safe range for a pediatric or adult patient.
How to Use Dimensional Analysis
Dimensional analysis (also called factor-label method) is the gold standard method taught in nursing programs for solving dosage calculations. The key principle: set up your equation so units cancel out, leaving only the unit you need in your answer.
Every solution shown in this tool walks through the dimensional analysis steps so you can see exactly how units cancel and where the numbers come from. This builds the systematic problem-solving approach that nursing programs and the NCLEX expect.
Looking for a conceptual review? Read our complete guide to nursing dosage calculations for formulas, worked examples, and study tips.
Disclaimer: This tool is for educational practice only. All problems are randomly generated with clinically realistic parameters. Always follow your facility's protocols, provider orders, and medication administration rights in clinical practice.
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