Use this free calculator to check common nursing drug calculations. Choose a calculation, enter your numbers and it shows the answer with the formula, so you can see how it was worked out. It is designed for nurses and nursing students to practise and double-check, not to replace your own calculation.
Enter the values to see the answer.
This calculator is a learning and double-checking aid. Always follow your local policy, check the prescription and product label, and have a second nurse check high-risk calculations.
The formulas
- Tablets: dose prescribed ÷ strength per tablet
- Liquids: (dose prescribed ÷ stock strength) × stock volume
- Weight-based dose: weight (kg) × dose per kg
- IV rate: volume (mL) ÷ time (hours) = mL/hr
- Drip rate: (volume × drop factor) ÷ time in minutes = drops/min
- mcg/kg/min to mL/hr: (dose × weight × 60) ÷ concentration in mcg/mL
Want worked examples and practice? Read drug calculation formulas with worked examples, paediatric weight-based dosing and the rights of medication administration.