Solution Dilution Calculator
How much stock and how much solvent — the solute is conserved, so only the volume changes.
The formula
C1 * V1 = C2 * V2 ; dilution factor = C1 / C2
Why the solute is conserved
Adding solvent changes the volume and nothing else, so the number of moles on each side of the equation is identical. That single fact is the whole of C₁V₁ = C₂V₂, and it is why the relation holds whatever units the concentration is quoted in — molar, percent or parts per million — provided both sides use the same one.
Serial rather than single
A single millionfold dilution would need one microlitre of stock measured into a litre of solvent, and the pipetting error would swamp the result. Six tenfold steps move a comfortable volume every time and arrive at the same place, which is why plate counts and standard curves are always built this way.
Which denominator?
Most of the confusion in solution work is not arithmetic but bookkeeping. Molarity divides by the volume of the finished solution; molality divides by the mass of the solvent; percent by mass divides by the mass of the solution again. The three agree closely in dilute water and diverge sharply in concentrated acid, which is why a bottle labelled 98 % is also labelled 18.4 M without contradiction.