Serial Dilution Calculator
Plan a serial dilution series and calculate the concentration at each step.
About Serial Dilution Calculator
Serial dilution achieves extreme dilutions accurately because each step stays within reliable pipetting volumes. Six tenfold steps give a millionfold dilution — six logs — which no single step could do precisely. Errors compound multiplicatively through a series, so a consistent 2 per cent pipetting error over six steps shifts the final concentration by about 13 per cent.
Formula
Serial Dilution
C_n = C₀ ÷ (dilution factor)^n; transfer volume = final volume ÷ dilution factor
- serial dilution
- Repeated small dilutions achieving a large total factor accurately
- log reduction
- Total dilution expressed as powers of ten
Worked example
With the default values below, Serial Dilution Calculator returns Concentration After the Last Step of 0.000001000000. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Starting concentrationminimum 0 mol/L
- 1 mol/L
- Dilution factor per stepaccepts 1.01–1,000 x
- 10 x
- Number of stepsaccepts 1–20
- 6
- Final volume per tubeminimum 1 uL
- 1,000 uL
Results
- Concentration After the Last Step
- 0.000001000000 mol/L
- Total Dilution Factor
- 1,000,000.00 x
- Volume to Transfer Each Step
- 100.000 uL
- Diluent per Tube
- 900.000 uL
- Log Reduction Achieved
- 6.0000
Step by step
- 1Values used
- 2Serial Dilution
- 3Concentration After the Last Step= 0.000001000000 mol/L
- 4Total Dilution Factor= 1,000,000.00 x
- 5Volume to Transfer Each Step= 100.000 uL
- 6Diluent per Tube= 900.000 uL
- 7Log Reduction Achieved= 6.0000
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 12 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Serial Dilution calculated?
C_n = C₀ ÷ (dilution factor)^n; transfer volume = final volume ÷ dilution factor Serial dilution achieves extreme dilutions accurately because each step stays within reliable pipetting volumes. Six tenfold steps give a millionfold dilution — six logs — which no single step could do precisely.
Why does Serial Dilution matter?
Errors compound multiplicatively through a series, so a consistent 2 per cent pipetting error over six steps shifts the final concentration by about 13 per cent.
What values do I need to enter?
This calculator takes 4 inputs: Starting concentration, Dilution factor per step, Number of steps, Final volume per tube. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.