Cell Dilution Calculator
Enter stock concentration, target concentration, and target final volume; the tool uses C₁V₁ = C₂V₂ to find the stock volume, diluent volume, and dilution factor, with a common dilution-factor reference table.
Input Data
Results
At a glance:Enter stock concentration, target concentration, and target final volume; the tool uses C₁V₁ = C₂V₂ to find the stock volume, diluent volume, and dilution factor, with a common dilution-factor reference table.
Formula
C₁V₁ = C₂V₂.
Stock volume V₁ = C₂V₂ / C₁.
Dilution factor = C₁ / C₂.
Diluent = V₂ − V₁.
$$C_1 V_1 = C_2 V_2$$$$V_1 = \dfrac{C_2 V_2}{C_1}$$How to Use
- Enter the stock concentration C₁, target concentration C₂, and final volume V₂.
- The calculator returns V₁, the diluent volume, and the dilution factor.
Common combinations with stock concentration 10 (units) and final volume 50 mL
| Target C₂ | Dilution factor | Stock V₁ (mL) | Diluent (mL) |
|---|---|---|---|
| 5 | 2 | 25.0000 | 25.0000 |
| 2 | 5 | 10.0000 | 40.0000 |
| 1 | 10 | 5.0000 | 45.0000 |
| 0.1 | 100 | 0.5000 | 49.5000 |
Stock concentration is fixed at 10 and final volume at 50 mL; lower target concentration means a larger dilution factor and less stock needed.
FAQ
Why does C₁V₁ = C₂V₂ hold?
Dilution only adds solvent; it does not change the amount of solute. The solute before dilution (C₁ × V₁) equals the solute after (C₂ × V₂), so they are equal and the formula solves for any unknown.
What units for concentration and volume?
As long as C₁ and C₂ use the same concentration unit (e.g. mg/mL, M, cells/mL) and V₁ and V₂ use the same volume unit (e.g. mL, µL), the formula holds. It is unit-agnostic as long as both sides are consistent.
Why can't the target concentration exceed the stock?
Dilution only lowers concentration. If the target is higher than the stock, you need concentration, not dilution; the formula does not apply, and the calculator returns a stock volume of 0 to indicate dilution is impossible.
What is the dilution factor?
Dilution factor = C₁ ÷ C₂, the multiple by which the stock is diluted. For example 10 to 2 gives a factor of 5, i.e. the '1:5 dilution' total factor of 5.
Why use serial dilution for very high factors?
A single very high factor (e.g. 1:1000) needs a tiny stock volume with large pipetting error. Serial dilution (10× per step, three steps) keeps each step's volume larger and more accurate — standard lab practice.
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References
Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.