Calculate transfer and diluent volumes for serial dilution series. Supports fold-based and custom concentration targets. Data never leaves your browser.
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Load example serial dilution data to see the full workflow
When to use
Do not use for
Each step uses the previous tube as its source, so a pipetting error in step 1 propagates to every subsequent step. Use calibrated pipettes, pre-wet tips, and consider independent dilutions from stock for critical reference standards.
Incomplete mixing is the #1 source of serial dilution error. Vortex or pipette-mix 5–10 times after adding diluent, before drawing the next transfer. This is especially important for viscous solutions.
After transferring sample to the next tube, the source tube volume decreases. If you need equal volumes for all tubes (e.g., for a plate reader), prepare extra volume in each tube or use a separate aliquot for the assay.
The diluent must be compatible with your downstream assay. For cell-based assays, use serum-free media. For ELISA, use assay buffer. For microbiology, use sterile PBS or broth. Water alone may lyse cells or alter pH.
All calculations use the dilution equation C₁V₁ = C₂V₂. In auto mode, target concentrations are generated as stock / fold^n for n = 1..N. Transfer volumes are computed as (C_target / C_source) V_total. Warnings fire when transfer < 1 µL or transfer > total volume.
Last validated 2026-04-05. Calculations are designed for planning and documentation support; verify procurement decisions against manufacturer specifications or institutional SOPs.
ConductScience Serial Dilution Planner (v1.0). ConductScience, Inc. 2026. Available at: https://conductscience.com/tools/serial-dilution-planner
Goldman E, Green LH. Practical Handbook of Microbiology. CRC Press. 2015.
Serial dilutions produce a geometric series of concentrations by repeatedly diluting a sample by a constant factor. The key equation is C₁V₁ = C₂V₂, where:
• C₁ = source concentration (previous tube or stock) • V₁ = volume transferred from source • C₂ = target concentration in the new tube • V₂ = total volume in the new tube
Rearranging: V₁ = (C₂ / C₁) V₂. The diluent volume is simply V₂ − V₁. Each tube in a serial dilution uses the previous tube as its source, so errors compound from step to step.
Match your dilution scheme to the experiment:
