Dilution Calculator (C1V1=C2V2)

The dilution calculator solves the standard laboratory relationship C1V1 = C2V2, used any time a concentrated stock solution needs to be diluted to a lower working concentration while keeping the total amount of dissolved solute constant. Given the Initial Concentration (C1) and Initial Volume (V1) of your stock solution, plus the Target Concentration (C2) you want to reach, the calculator solves directly for the Final Volume (V2): V2 = C1V1 / C2. Because diluting a solution means adding solvent, not solute, the total moles present (concentration times volume) stays fixed on both sides of the equation -- that conservation is the entire physical basis for the formula. Solvent to Add reports V2 minus V1: how much diluent you actually need to pour in, on top of the stock you started with, to land at your target concentration.

Dilution Factor (C1/C2, unitless) expresses how many times more concentrated the stock is than your target -- a factor of 10 means the finished solution is a tenth as concentrated as what you started with, which is useful when scaling a protocol or comparing serial dilutions. Note that the equation assumes ideal mixing with no significant volume-of-mixing effects, which holds well for dilute aqueous solutions but can break down for concentrated acids or solvents that measurably shrink or expand on mixing. It also requires Target Concentration to be lower than Initial Concentration: diluting can only reduce concentration by adding solvent, never raise it, so entering a Target Concentration above your stock's concentration will not produce a physically meaningful Final Volume.