Serial Dilution Calculator
f = (C₀ / Cₙ)^(1/n), V_transfer = V_tube / f
Plan a dilution series as a visual tube or plate map: transfer volume, diluent volume and concentration for every step.
Step 1 — Define the series
How the concentrations should step down, and in what kind of vessel.
10 means a 1:10 dilution at each step.
Excludes the starting tube.
Step 2 — Define volumes
Total volume in each vessel, and what you dilute into.
Label only — used in the transfer instructions.
Step 3 — Review the dilution map
Start, each transfer and the final concentration at a glance.
Dilution map
Start1 MEnd10 µMTransfers5Each step1:10Per tube1 mLDiluentbuffer
Tube 1 · stock
1 M
100 µL from Tube 1
+ 900 µL buffer
- 1:10
Tube 2
100 mM
100 µL from Tube 2
+ 900 µL buffer
- 1:100
Tube 3
10 mM
100 µL from Tube 3
+ 900 µL buffer
- 1:1000
Tube 4
1 mM
100 µL from Tube 4
+ 900 µL buffer
- 1:10000
Tube 5
100 µM
100 µL from Tube 5
+ 900 µL buffer
- 1:1 × 10⁵
Tube 6
10 µM
Step-by-step instructions
- Start with Tube 1 at 1 M.
- Transfer 100 µL from Tube 1 into Tube 2, add 900 µL buffer and mix thoroughly.
- Transfer 100 µL from Tube 2 into Tube 3, add 900 µL buffer and mix thoroughly.
- Transfer 100 µL from Tube 3 into Tube 4, add 900 µL buffer and mix thoroughly.
- Transfer 100 µL from Tube 4 into Tube 5, add 900 µL buffer and mix thoroughly.
- Transfer 100 µL from Tube 5 into Tube 6, add 900 µL buffer and mix thoroughly.
- Tube 6 is the endpoint at 10 µM.
Shading follows concentration — darker is more concentrated.
Reagent summary — prepare before you start
- Total stock needed
- 0.1 mL
- Total buffer needed
- 4.5 mL
- Tubes used
- 6
- Concentration range
- 1 → 1.00 × 10⁻⁵ mol/L
- Carried to next vessel
- 0.4 mL
- Volume left in last vessel
- 1 mL
Aliquot taken from the starting solution
Sum across all steps
Including the starting vessel
Removed again from intermediate vessels
Add a pipetting allowance if your vessels have significant dead volume.
Step 4 — Results and per-step detail
Formulae, substituted values and the full step table.
Result
1 : 10 per step
Final concentration after 5 steps: 1.00000 × 10⁻⁵ mol/L
Calculation
Dilution factor per step
f = entered dilution factor
f = 10
Transfer volume per tube
V_transfer = V_tube / f
V_transfer = 1 mL / 10
V_transfer = 0.1 mL
Diluent volume per tube
V_diluent = V_tube − V_transfer
V_diluent = 0.9 mL
Inputs
- Initial concentration
- 1 mol/L
- Dilution factor
- 1 : 10
- Steps
- 5
- Volume per tube
- 1 mL
Each tube is mixed thoroughly before the next transfer. Volumes assume the transfer volume is included in the stated tube volume.
Per-step detail
| Tube | Start (mol/L) | Transfer (mL) | buffer (mL) | Total (mL) | Final (mol/L) |
|---|---|---|---|---|---|
| Tube 2 | 1 | 0.1 | 0.9 | 1 | 0.1 |
| Tube 3 | 0.1 | 0.1 | 0.9 | 1 | 0.01 |
| Tube 4 | 0.01 | 0.1 | 0.9 | 1 | 0.001 |
| Tube 5 | 0.001 | 0.1 | 0.9 | 1 | 0.0001 |
| Tube 6 | 0.0001 | 0.1 | 0.9 | 1 | 1.00000 × 10⁻⁵ |
About this calculator
A serial dilution applies the same dilution factor repeatedly. Either enter the factor directly (for example 10 for a 1:10 series) or enter a target final concentration, in which case the required per-step factor is derived as the n-th root of the total dilution.
For each tube or well the transfer volume is the vessel volume divided by the factor, and the diluent volume is the remainder. Mix each vessel thoroughly before transferring to the next one; the dilution map shows the full path, with darker shading for higher concentrations.
Because every intermediate vessel gives up its transfer volume to the next one, the reagent summary lists the total stock and diluent to prepare before you start.
LabReadyTools is provided as a calculation aid. Users remain responsible for verifying calculations, units, chemical compatibility, experimental procedures and applicable safety requirements before laboratory use.
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