Dilution Calculator
Use C1V1 = C2V2 to prepare lab dilutions.
C₁V₁ = C₂V₂ solved in any direction, plus a full serial-dilution series. Concentration and volume units are converted internally, so mM with L and M with µL both give the right answer.
Dilution changes concentration and volume but never the number of moles of solute already in the flask.
How to Use the Dilution Calculator
1
Choose what to solve for. Pick stock volume, final concentration, final volume, stock concentration, or a full serial dilution series.
2
Enter concentrations and volumes. Type the three known values with their units; mixed units are converted internally.
3
Follow the preparation note. The result gives the answer, the volume of solvent to add, the dilution factor, and the unchanged number of moles of solute.
What is the Dilution Calculator?
The dilution calculator applies C1V1 = C2V2 to solve stock-solution problems: how much concentrated stock you need, what final concentration a dilution produces, or the dilution factor between two solutions. Units are converted automatically so mL and L inputs can be mixed safely.
Dilution is the single most common calculation at a lab bench. Getting V1 right before you pipette saves reagents and repeat runs, and the calculator's step display doubles as a written procedure for your lab notebook.
Common Uses
- Find stock volume needed for a target concentration
- Calculate final concentration after dilution
- Work out dilution factors for serial dilutions
- Prepare buffers and standards from concentrates
How to Solve It by Hand
Manual calculation is still important: identify the known variables, convert units before substitution, apply the equation, and check whether the result is chemically reasonable. The most common mistakes are inconsistent units, constants rounded too early, and skipping the interpretation step.
What is Dilution Factor?
Dilution factor tells how many times more dilute the final solution is compared with the original stock solution. A dilution factor of 10 means the final solution is 10 times less concentrated than the stock, often written as a 1:10 dilution.
It is used when a strong solution is too concentrated for direct use. In chemistry and biology labs, students use dilution for preparing standard solutions, making serial dilutions, reducing acid or base concentration, preparing stains or buffers, and bringing a sample into the measurable range of an instrument such as a spectrophotometer.
How to Calculate Dilution Factor Manually
- Write the known values. Identify the stock concentration, final concentration, stock volume, and final volume.
- Use matching units. Concentrations must match each other, and volumes must match each other. For example, use mL with mL or L with L.
- Choose the correct relationship. Dilution factor can be calculated as final volume divided by stock volume: DF = V2 / V1. It can also be calculated as stock concentration divided by final concentration: DF = C1 / C2.
- Substitute the numbers. If 10 mL of stock is diluted to a final volume of 100 mL, then DF = 100 / 10 = 10.
- Interpret the answer. The final solution is a 1:10 dilution, so it is 10 times less concentrated than the original stock.
Relatable Lab Example
Suppose a lab has 1.0 M copper sulfate stock solution, but the experiment needs 0.10 M copper sulfate for a color-intensity test. Because DF = C1 / C2, the dilution factor is 1.0 / 0.10 = 10. To make 100 mL of the diluted solution, use V1 = V2 / DF = 100 mL / 10 = 10 mL of stock, then add water until the total volume reaches 100 mL.
This is the same idea as making a strong drink or syrup weaker by adding water, except in the lab the final volume and concentration must be measured carefully so the experiment is repeatable.
Practice Prompt
Try changing the default values and ask the lower-right chemistry chat why the result increased or decreased. That turns the calculator from a number machine into a study loop.
C₁V₁ = C₂V₂. Dilution adds solvent without changing the number of moles of solute, so the product of concentration and volume is the same before and after.
Rearrange to V₁ = C₂V₂ / C₁. To make 100 mL of 0.1 M from a 1 M stock: (0.1 × 100) / 1 = 10 mL of stock, then add solvent up to 100 mL total.
The dilution factor is how many times weaker the final solution is: DF = C₁/C₂ = V₂/V₁. A factor of 10 is written as a 1:10 dilution and means the solution is ten times less concentrated.
Each step dilutes by the same factor, so after n steps the concentration is C₀ divided by DFⁿ. A 1:10 series reaches a millionfold dilution in six tubes. The serial mode builds the full tube-by-tube table.
The two concentrations must be in the same unit as each other, and the two volumes in the same unit as each other. This calculator converts everything internally, so mM with L and M with µL both give the right answer.