What is the Dilution Calculator?
Diluting a stock solution is one of the most common lab calculations. The dilution equation C₁V₁ = C₂V₂ relates the concentration and volume before dilution (stock) to the concentration and volume after dilution (final). Enter any three values and this calculator solves the fourth — plus the dilution factor and how much solvent to add. Volumes can be entered in µL, mL, or L. Concentrations use mol/L (molarity). Everything runs instantly in your browser with no signup.
How to use the Dilution Calculator
- Choose which variable to solve: final volume, final concentration, stock volume, or stock concentration.
- Enter the three known values for C₁, V₁, C₂, and V₂.
- Select your volume unit (µL, mL, or L).
- Read the solved value, dilution factor, and solvent volume to add.
- Copy the summary for your lab notebook.
Common use cases
- Diluting 100 mL of 1 M stock to 0.25 M and finding the final volume
- Calculating how much 6 M HCl to pipette for 1 L of 0.5 M solution
- Finding the final concentration after combining a known stock volume and diluent
Frequently asked questions
- What is the dilution formula?
- C₁V₁ = C₂V₂, where C is concentration (mol/L) and V is volume. Subscript 1 is the stock solution; subscript 2 is after dilution.
- How is dilution factor calculated?
- Dilution factor = C₁ / C₂ (or V₂ / V₁). A 1 M stock diluted to 0.25 M has a 4× dilution factor.
- How much solvent do I add?
- Solvent to add = V₂ − V₁ (final volume minus stock volume), assuming you add solvent to the stock aliquot to reach the final volume.
