Drug Dilution Calculator
Solve C₁V₁ = C₂V₂ for stock volume, diluent, final concentration or volume.
Enter your values to see the result.
Uses C₁V₁ = C₂V₂, which holds when you dilute with a solvent that contains none of the drug. Both concentrations must be in the same unit. For education and clinical decision support only. Results do not replace professional judgment, local protocols or the product information, so always verify doses and values before acting on them.
Continue your work
- IV Infusion Rate Calculator — Set the pump rate for the diluted drug.
- Drug Dose Calculator — Work out the dose first.
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How to use the Drug Dilution Calculator
Solve C₁V₁ = C₂V₂ for stock volume, diluent, final concentration or volume.
- 1 Choose which value to solve for.
- 2 Enter the other three values, with both concentrations in the same unit.
- 3 Read the result, the diluent to add and the dilution factor.
Example and practical tips
To make 250 mL of a 2 mg/mL solution from a 50 mg/mL stock, take 10 mL of stock and add 240 mL of diluent.
Frequently asked questions
Is V2 the diluent volume?
No. V2 is the final total volume. The diluent to add is V2 − V1.
Can I mix units?
No. Both concentrations must use the same unit, and both volumes the same unit, for the formula to work.
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