Enter the starting concentration, a whole number of tenfold dilution steps, and the sample transfer volume to calculate the final concentration and diluent required.

Calculate the concentration after a whole number of tenfold steps.

Each step mixes one volume of sample with nine volumes of diluent, then mixes thoroughly before the next transfer.

Whole steps, 0–308. Zero steps leaves concentration unchanged.

Used when at least one dilution step is performed.

10-Fold Dilution Formula

The following formula is used to calculate the final concentration after a 10-fold dilution.

C2 = C1 / D, D = 10ⁿ

Variables:

  • C2 is the final concentration after dilution
  • C1 is the initial concentration before dilution
  • D is the cumulative dilution factor: 10 for one step or 10ⁿ for n whole tenfold steps

To calculate the final concentration after a 10-fold dilution, divide the initial concentration by the dilution factor.

What is a 10-Fold Dilution?

A 10-fold dilution is a process in which a substance is diluted to one-tenth of its original concentration. This is typically done by taking one part of the substance and adding nine parts of a diluent, such as water or another solvent. The result is a solution that is 10 times less concentrated than the original. This process can be repeated multiple times to achieve even lower concentrations.

How to Calculate 10-Fold Dilution?

The following steps outline how to calculate a 10-Fold Dilution.

  1. First, determine the initial concentration before dilution (C1).
  2. Next, determine the dilution factor (D). In this case, the dilution factor is 10 for a 10-fold dilution.
  3. Next, use the formula C2 = C1 / D to calculate the final concentration after dilution (C2).
  4. Finally, calculate the 10-Fold Dilution by inserting the values of C1 and D into the formula and solving for C2.
  5. After calculating the result, check your answer for accuracy.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Initial concentration before dilution (C1) = 50

Dilution factor (D) = 10

The final concentration is 50 ÷ 10 = 5 in the same concentration unit. For a 1 mL transfer, add 9 mL of diluent to prepare 10 mL. Three repeated steps give D = 1,000. Zero steps gives D = 1 and leaves the starting concentration unchanged. Thorough mixing, analyte-free diluent and no analyte loss or gain are assumed.