labmatetools / 2.4 SERIAL DILUTION ALL TOOLS

Serial Dilution Calculator

Set the top concentration, the fold and how many tubes. You get what goes into every tube, the concentration series, and a plan to print.

SECTION 02 — CALCULATORS · 2.4SET → PLAN → PIPETTE

C1TOP CONCENTRATION
÷FFOLD PER STEP
-fold
nTUBES IN SERIES
tubes
VLEFT IN EACH TUBE
CsSTOCK · OPTIONAL
TUBE CONCENTRATION DILUENT ADD ENDS WITH
HOW TO
    SERIES
    1. HIGHEST—
    2. LOWEST—
    3. TRANSFER—
    4. DILUENT NEEDED—
    ABOUT THIS TOOL

    How to use

    1. Enter the concentration you want in the first tube — the top of your series or standard curve.
    2. Pick the fold per step (2× for a half-dilution, 10× for a log series) and how many tubes.
    3. Enter how much you need left in each tube for your assay.
    4. If the top tube must itself be made from a stronger stock, enter the stock. The plan adds that step.
    5. Follow the steps: diluent into every tube first, then transfer and mix from tube to tube. Change tips between tubes.
    6. COPY PLAN pastes into Excel or your notebook; PRINT gives a one-page bench sheet.

    The formula

    Ck = C1 ÷ Fk−1
    transferT = V ÷ (F − 1)
    diluentD = V (tubes 2 to n)
    tube 1V + T of the top concentration

    Each tube gets D of diluent plus T from the tube before: (T + D) ÷ T = F.

    Example. 6 tubes, 2-fold, 100 µL each from 1000 ng/mL: put 100 µL diluent in tubes 2–6, 200 µL of 1000 ng/mL in tube 1, then move 100 µL down the line → 1000, 500, 250, 125, 62.5, 31.25 ng/mL.

    Good to know

    1. Free to use. No subscription. Nothing you type leaves your browser.
    2. Errors add up along a series — mix well and change tips at every step.
    3. Volumes are rounded to 4 significant figures.
    QUESTIONS · SERIAL DILUTION CALCULATOR

    Frequently asked

    How much do I transfer between tubes in a serial dilution?

    Transfer T = V ÷ (F − 1), where V is the volume you want left in each tube and F is the fold. Tubes 2 to n each get V of diluent first.

    What does a 2-fold, 6-tube series from 1000 ng/mL look like?

    With 100 µL per tube: 100 µL diluent in tubes 2–6, 200 µL of 1000 ng/mL in tube 1, then move 100 µL down the line — 1000, 500, 250, 125, 62.5 and 31.25 ng/mL.

    My top tube has to be made from a stronger stock. Can it plan that?

    Yes. Enter the stock concentration and the plan adds the step that makes the top tube.

    Can every tube end with the same volume?

    Yes. Tick the option to take the extra out of the last tube. You can also add a blank tube with diluent only.