Dilution Calculator
Solve C₁V₁ = C₂V₂ for any missing concentration or volume.
About the Dilution Calculator
Choose the value to find and enter the other three. The result also tells you how much solvent to add to the stock, which is the step you actually do at the bench.
Diluting doesn't change the amount of solute, so concentration × volume is the same before and after. Use any units, as long as both concentrations share one unit and both volumes share another.
The formula
C₁ V₁ = C₂ V₂
- C₁, V₁
- stock concentration and the volume of stock you use
- C₂, V₂
- the concentration and total volume you want
Worked example
Make 100 mL of 0.5 M from a 2 M stock
- V₁ = 0.5 × 100 ÷ 2 = 25 mL of stock
- Add 75 mL of solvent to reach 100 mL
- That's a 1 in 4 dilution
Questions people ask
Does this work for percentages?
Yes, for % w/v or v/v as well as molarity.
Is it exact for mixing liquids?
Volumes aren't always additive (e.g. ethanol and water), so make up to the final volume.