Serial Dilution Scheme Designer

What this is for: Designs a serial dilution between two concentrations: how many steps, and the transfer + diluent volume for every tube.

The formula: steps = log(start ÷ target) ÷ log(dilution factor per step)

How to use:

Enter the stock concentration and the target concentration, keeping units consistent (e.g. both in ng/µL).
Choose the dilution factor per step (2, 3, 5 or 10).
Enter the final volume per tube (mL).
Read the steps needed to reach the target.
Use the table for the concentration, transfer (µL), diluent (µL) and cumulative dilution at each step.

Designs a constant-factor scheme: steps needed to reach a target concentration, plus the transfer and diluent volume for every tube. Keep units consistent between stock and target (e.g. both in ng/µL).

Stock concentration

Target concentration

Dilution factor per step

Final volume per tube (mL)

Steps needed to reach target

Step

Concentration

Transfer (µL)

Diluent (µL)

Cumulative dilution

Prefer to work offline or keep a copy? The download link is right below.
Download the Serial Dilution Scheme Designer workbook (.xlsx)

Notes & limits (from the workbook): Designs a constant-factor scheme: steps needed to reach a target concentration, plus the transfer and diluent volume for every tube. Keep units consistent between stock and target (e.g. both in ng/µL). Steps needed = CEILING(LOG(stock/target) / LOG(factor)). The workbook table runs to step 12; if your target needs more steps, extend the same pattern.