Stock Solution Dilution Calculator (Serial Dilution)

Use a single dilution when one transfer into a final vessel achieves your target. For very low targets, a serial plan improves practical accuracy by chaining several simple dilutions. A step factor (e.g., 10×) tells you how much to transfer relative to the tube’s working volume; factors compound across steps so that the overall dilution equals the product of all step factors.

This tool converts your chosen units to internal base units, applies the identities C₁V₁=C₂V₂ (single) or S/T=∏fᵢ (serial), and then reports volumes in your selected volume unit. Optional constraints include a tube dead volume, a minimum pipet volume, and rounding to realistic increments. If any step violates constraints or yields negative diluent, you’ll see a badge so you can tweak factors, working volume, or rounding.

Single: V_stock = (C_target·V_final)/C_stock;   V_diluent = V_final − V_stock.
Serial overall: F = S/T = ∏ f_i.   For fixed f, steps k ≈ ceil(log(F)/log(f)).
Per step i (working volume V_work): Transfer = V_work/f_i;   Diluent = V_work − Transfer.
Units: M→base 1, mM=1e−3, µM=1e−6, nM=1e−9; mg/mL, µg/mL, and % are treated consistently as entered (ratios cancel). Volumes normalized internally (µL/mL/L) then reconverted for display.

Why serial? It reduces pipetting tiny volumes, improving precision at very low targets.

What is working volume? The total volume in each tube after mixing transfer+diluent.

What if a step is below my pipet’s minimum? Increase working volume, change factors, or enable rounding.

Why do I see scientific notation? Very small numbers are rendered that way for clarity.