Everyday serial dilution problems come down to one relationship between volume of dilutant to be added, volume of dilutant to be added, dilution factor, number of dilutions, percentage error, volume per use, starting solution concentration, pipette error, number of uses per dilution, stock solution concentration, stock solution concentration and one way. This calculator turns those numbers into volume of stock solution required, starting volume needed and volume to be moved at each step, with the working shown so you can check the result rather than simply trust it.
What Is the Serial Dilution Calculator?
The serial dilution calculator turns volume of dilutant to be added, volume of dilutant to be added, dilution factor, number of dilutions, percentage error, volume per use, starting solution concentration, pipette error, number of uses per dilution, stock solution concentration, stock solution concentration and one way into volume of stock solution required, starting volume needed and volume to be moved at each step.
It is a quick way to get from the numbers you have to the number you need, without setting up a spreadsheet or reaching for a formula.
How the Serial Dilution Works
Each result follows from the ones before it, and the calculator shows every step, so a surprising answer can be traced back to the input that caused it.
Round your inputs to the precision you actually know, and keep more precision than that in the intermediate steps.
Getting a Result You Can Trust
Run the calculation twice with slightly different inputs. A sensible calculator moves its output in proportion; a wild change points to a unit or a decimal point problem in what you entered.
Write the inputs down next to the answer. It takes a moment and it is the difference between a number you can explain and one you cannot.
A Worked Example
Working through an example, with volume of dilutant to be added set to 10, volume of dilutant to be added set to 5, dilution factor set to 2, the calculator returns minimum volume required of 55, and volume to be moved at each step of 55, and dilutant needed at each step of 55. Substitute your own figures and the same steps produce the same kind of answer.
Frequently Asked Questions
What do I need to work out volume of stock solution required?
Enter volume of dilutant to be added, volume of dilutant to be added, dilution factor, number of dilutions, percentage error, volume per use, starting solution concentration, pipette error, number of uses per dilution, stock solution concentration, stock solution concentration and one way. The calculator then works through the relationship and reports volume of stock solution required, starting volume needed and volume to be moved at each step.
What does the serial dilution actually calculate?
It takes volume of dilutant to be added, volume of dilutant to be added, dilution factor, number of dilutions, percentage error, volume per use, starting solution concentration, pipette error, number of uses per dilution, stock solution concentration, stock solution concentration and one way and converts them into volume of stock solution required, starting volume needed and volume to be moved at each step using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.
How should I enter volume of dilutant to be added?
Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.
Do I have to fill in every field?
Only the fields a particular result depends on. If you leave one blank, the results that need it simply show a note instead of a number, and everything else still works.
Why does a small change in one value move the answer so much?
That happens when an output depends on a ratio, because dividing by a small number magnifies any change in it. Check the units first, then check whether the value you entered is in the range the relationship was designed for.