How to use the Dilution Calculator
Choose the quantity you need in Solve for, enter the other three values, and click Calculate. The result shows the selected value, Formula & steps, and Diluent to add when both volume values allow that subtraction.
- Choose Stock concentration (C₁), Stock volume (V₁), Target concentration (C₂), or Final volume (V₂) in Solve for.
- Enter the other three positive values and choose a Unit for each concentration and volume field.
- Keep Stock concentration (C₁) and Target concentration (C₂) in the same family, either molar or mass-based.
- Click Calculate, then read Result and Formula & steps. Use Copy result or Download result (.txt) for the plain-text calculation.
- Click Reset to clear the values, restore the initial selections, and hide the previous result.
How to calculate a dilution with C₁V₁ = C₂V₂
C₁ is Stock concentration, V₁ is Stock volume, C₂ is Target concentration, and V₂ is Final volume. The calculator puts concentration values on a matching molar or mass-based basis and volumes in liters before rearranging the equation for the quantity selected in Solve for.
Input:
Solve for: Final volume (V₂)
Stock concentration (C₁): 2 M
Stock volume (V₁): 25 mL
Target concentration (C₂): 0.5 M
Output:
Final volume (V₂): 100 mL
Diluent to add: 75 mLDilution calculator units and concentration families
Concentration fields accept mol/L (M), mmol/L (mM), µmol/L (µM), mg/mL, g/L, and % w/v. Volume fields accept Liters (L), Milliliters (mL), and Microliters (µL). Choose molar units for both concentration fields or mass-based units for both. The calculator does not convert between those families because it has no molar mass for the solute.
What the dilution result shows
Result shows the selected quantity. Formula & steps lists the equation, supplied values, calculation on the normalized basis, and result. Individual unit conversions are not listed. When both volumes are available and V₂ is at least V₁, the result also shows V₂ − V₁ as Diluent to add. If V₁ exceeds V₂, the calculator omits that statistic.
What dilution calculator input errors mean
Enter decimal numbers greater than zero. Blank, non-numeric, zero, negative, non-finite, and larger-than-1e12 values are rejected. Scientific notation is rejected as well. A molar concentration paired with a mass-based concentration also causes an error. The calculation assumes a constant solute amount, additive volumes, and uniform concentration after mixing, so it does not model temperature effects, density, volume contraction, or solute-solvent interactions.
Entered values and the calculation stay in your browser. The page does not send them in a network request.
Where this dilution calculation comes up
- You know Stock concentration (C₁) and Target concentration (C₂), and need Stock volume (V₁) for a chosen Final volume (V₂).
- You need Diluent to add after solving for Final volume (V₂) from the other three values.
- You have a concentration in g/L and keep both concentration fields in the mass-based family.
When another science calculator fits better
Use the Science Calculators category for a different science relationship. Use the Molarity Calculator for moles or mass of solute and solution volume. The Chemistry Calculator covers pH, molar mass, stoichiometry, solution preparation, and its other listed calculations. Use the Beer-Lambert Law Calculator for absorbance, concentration, path length, or absorptivity.
Frequently asked questions
What is the dilution formula?
C₁V₁ = C₂V₂ relates Stock concentration and Stock volume to Target concentration and Final volume.
Can I solve for stock volume with the Dilution Calculator?
Choose Stock volume (V₁) in Solve for and enter Stock concentration (C₁), Target concentration (C₂), and Final volume (V₂).
Which units can I use for a dilution?
Use M, mM, µM, mg/mL, g/L, or % w/v for concentration, plus L, mL, or µL for volume. Stock concentration (C₁) and Target concentration (C₂) must use the same family.
How do I calculate how much diluent to add?
The calculator shows Diluent to add as V₂ − V₁ when both volumes are available and V₂ is at least V₁. It omits that statistic when Stock volume (V₁) is greater.
Does the Dilution Calculator account for mixing or temperature effects?
It assumes additive volumes and uniform concentration after mixing. It does not model temperature, density, volume changes, or solute-solvent interactions.