How It Works
This planner works in 4 steps.
Enter the total dilution
Type the overall DF or the start and end concentrations.
Choose the stage count
Select 2 to 6 stages, or let the planner choose the fewest stages within the pipette limits.
Set volume limits
Type the final volume per stage and the minimum and maximum transfer volumes.
Read the stage table
The planner lists the factor, transfer, diluent, and concentration for each stage.
The Formula
The formula takes the n-th root of the total factor for equal stages.
F = DF_total^(1/n)V_t = V_stage / Fn_min = ⌈log(DF_total) / log(F_max)⌉- DF_total:
- Overall dilution factor
- n:
- Number of stages
- F:
- Factor per stage
- V_stage:
- Final volume per stage
- F_max:
- Largest factor the volume limits allow
A 1:10⁶ dilution in 3 stages uses F = 100 per stage. With 1 mL per stage, each stage takes 10 µL into 990 µL.
Conversion Table
The conversion table shows equal stage factors and the transfer volume per 1 mL stage for 6 total dilutions.
| Total DF | Stages | Factor per stage | Transfer per stage |
|---|---|---|---|
| 10,000 | 2 | 100 | 10 µL in 1 mL |
| 10⁶ | 3 | 100 | 10 µL in 1 mL |
| 10⁶ | 2 | 1,000 | 1 µL in 1 mL |
| 10⁸ | 4 | 100 | 10 µL in 1 mL |
| 50,000 | 3 | 36.84 | 27.14 µL in 1 mL |
| 2 × 10⁵ | 4 | 21.15 | 47.29 µL in 1 mL |
What Is the Multistage Dilution Planner?
The Multistage Dilution Planner is a tool that divides one large dilution into 2 to 6 sequential stages and returns the factor, transfer volume, and diluent volume for each stage. The planner keeps every transfer inside the user's pipette range.
One-step dilutions above 1:1,000 waste diluent or need tiny transfers. A 1:10⁶ dilution in 1 step needs 1 µL in 1 L (0.26 US gal). In 3 equal stages of 1:100, each stage needs 10 µL in 1 mL. The planner suggests equal factors first and then adjusts to round, pipette-friendly volumes.
Common Uses
There are 5 main uses of this planner.
Trace-level standards
Analysts bring mg/L stocks to ng/L levels for ICP-MS.
Phage and virus dilution
Virologists dilute 10¹⁰ PFU/mL stocks into countable ranges.
High-titer antibody work
Users dilute concentrated antibodies to 1:100,000 for sensitive detection.
Environmental samples
Labs dilute high-strength wastewater samples for discrete analyzers.
Pipette-limited labs
Teaching labs with only P200 and P1000 pipettes plan stages within those ranges.