Dilution Factor Calculator — C₁V₁ = C₂V₂
Find the dilution factor between stock and final solution, or calculate how much diluent to add — using concentration mode or volume mode.
Calculate using
mL
1 : 10 (1 part stock to total parts)
- 1
Initial concentration (C₁)
100 - 2
Final concentration (C₂)
10 - 3
Dilution factor = C₁ ÷ C₂
100 ÷ 10 = 10
How does this calculator work?
Dilution factor = C₁/C₂ = V₂/V₁. Use C₁V₁ = C₂V₂ to find any missing value: if you know the stock concentration and the target concentration, the DF tells you how to split volumes. Enter two of the four quantities and the formula gives the rest. Units can be anything — keep them consistent.
Formula
How this is calculated
A dilution factor (DF) expresses how many times more concentrated the original stock solution is compared to the final diluted solution. If you have 100 mg/mL and dilute it to 10 mg/mL, the DF is 10 (or "1:10"). The conservation-of-mass equation C₁V₁ = C₂V₂ links any two values among initial concentration, initial volume, final concentration, and final volume: knowing any three lets you solve for the fourth.
In concentration mode, you enter C₁ and C₂; the calculator gives DF = C₁/C₂. If you also specify the stock volume V₁ taken, it shows the total volume needed (V₂ = DF × V₁) and the volume of diluent to add (V₂ − V₁). In volume mode you specify V₁ and V₂; the calculator derives DF = V₂/V₁ and the resulting final concentration C₂ = C₁V₁/V₂.
The units of concentration can be anything — mg/mL, mM, %, copies/μL — as long as C₁ and C₂ use the same unit. The diluent is assumed to contribute negligible solute (zero initial concentration). For serial dilutions the same DF applies at each step; the equivalent number of 10-fold steps is log₁₀(DF).
Frequently asked questions
A dilution factor of 10 means the final concentration is one-tenth of the original. In practice, you take 1 part stock and add 9 parts diluent to reach a total of 10 parts — a "1 in 10" or 1:10 dilution.
A serial dilution applies the same dilution factor repeatedly to a sample. A series of five 1:10 dilutions produces a 1:100,000 (10⁵) overall dilution. Serial dilutions are common in microbiology, immunology, and analytical chemistry to cover a wide concentration range.
Yes, as long as C₁ and C₂ are in the same units and V₁ and V₂ are in the same units. The equation expresses conservation of solute mass (or moles): the amount of solute before and after dilution is the same, assuming the diluent contains none of the solute.
Also known as
TG we-Calculate Editorial Team. (2026). Dilution Factor Calculator — C₁V₁ = C₂V₂ [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/dilution-factor-calculator
TG we-Calculate Editorial Team. "Dilution Factor Calculator — C₁V₁ = C₂V₂." TG we-Calculate. 2026. https://we-calculate.com/calculator/dilution-factor-calculator.
TG we-Calculate Editorial Team, "Dilution Factor Calculator — C₁V₁ = C₂V₂," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/dilution-factor-calculator
@misc{wecalculate_dilution_factor_calculator, title = {Dilution Factor Calculator — C₁V₁ = C₂V₂}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/dilution-factor-calculator}}, year = {2026}, note = {TG we-Calculate} }
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