Dilution Calculator: C1V1, C2V2 and Serial Dilutions

Dilution Calculator

Solve C₁V₁ = C₂V₂ for one unknown or generate a serial-dilution table with concentration, per-step factor and cumulative factor.

Leave exactly one of the four values empty. Both concentrations must use the selected concentration unit and both volumes the selected volume unit.

Dilution formulas

For an ideal dilution in which the amount of solute transferred is conserved:

C₁V₁ = C₂V₂.

Therefore V₁ = C₂V₂ ÷ C₁, C₂ = C₁V₁ ÷ V₂, and the dilution factor is C₁ ÷ C₂ = V₂ ÷ V₁.

For a serial dilution with transfer volume t and diluent volume d: factor per step = (t + d) ÷ t, and concentration after step n is C₀ ÷ factorⁿ.

Scope and safety: concentrations must use the same basis before applying C₁V₁ = C₂V₂. The formula assumes solute conservation and ideal volume behavior. It does not account for reactions, density contraction, assay/purity corrections, activity, pH, temperature or instrument uncertainty. Follow the reagent SDS and laboratory procedure; never infer a safe mixing order from this calculator.

Six calculated examples

InputsCalculated result
10 M stock; 0.1 M target; 500 mL finalV₁ = 5 mL stock; 495 mL volume difference; factor 100
2 M stock; 25 mL stock; 100 mL finalC₂ = 0.5 M; factor 4; 75 mL volume difference
Unknown C₁; V₁ = 10 mL; C₂ = 0.2 M; V₂ = 100 mLC₁ = 2 M; factor 10
5 M stock; V₁ = 4 mL; C₂ = 0.1 MV₂ = 200 mL; 196 mL volume difference
1 M start; transfer 1 mL + 9 mL diluent; 3 steps0.1 M, 0.01 M, 0.001 M; cumulative factor 1,000
1,000 µM start; transfer 200 µL + 800 µL diluent; 4 steps200, 40, 8 and 1.6 µM; cumulative factor 625

How to use the dilution calculator

  1. For one dilution, choose units and leave exactly one of C₁, V₁, C₂ or V₂ empty.
  2. Use the same concentration basis for C₁ and C₂. For example, do not mix molarity with mass percent.
  3. Use the same volume unit for V₁ and V₂. The solved result remains in that selected unit.
  4. For a serial dilution, enter the concentration before the first step, the aliquot transferred, fresh diluent per vessel and number of steps.
  5. Check that the planned transfer volume is practical for the available calibrated equipment and that the protocol specifies adequate mixing.

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