Solution Dilution Calculator
Find the stock aliquot for a target concentration and volume, or predict concentration after dilution.
01 Set up your calculation
- Choose to calculate a stock aliquot or the final concentration.
- Enter the stock concentration and the required final volume.
- For a preparation, take the calculated aliquot and make up to the final volume using a suitable diluent.
02 The relationship
For the assumptions behind these results, read the explanation below. You can also explore Dilution Factor and Serial Dilution.
Follow the numbers
To make 100 mL of 0.1 mol/L solution from a 1 mol/L stock, take 10 mL of stock and make up to 100 mL. If volumes add, the diluent amount is 90 mL.
03 The solute amount stays the same
Dilution adds solvent while retaining the solute carried by the stock aliquot. Multiplying concentration by volume gives that solute amount before and after dilution. Equating the two quantities gives the familiar C₁V₁ = C₂V₂ relationship.
The equation requires consistent concentration definitions. It works directly for amount or mass per solution volume, but a mass percentage needs a mass balance or density conversion rather than being inserted as if it were molarity.
04 Make up to the final volume
Final volume includes the stock aliquot. Adding the entire final-volume value as diluent on top of the aliquot produces too much solution and too low a concentration. The result therefore separates stock amount, approximate added diluent, and final total.
For accurate volumetric work, use a measured final volume because mixed liquid volumes are not always additive. The tool assumes no reaction, precipitation, evaporation, or solute loss. It also cannot turn a weaker stock into a stronger target by adding diluent; such inputs are rejected.
Questions from the notebook
Can the target equal the stock concentration?
Yes. The stock aliquot then equals the final volume and no dilution is required.
What does a zero target produce?
It produces zero stock aliquot and a preparation consisting entirely of diluent in this ideal balance.
Can I prepare a more concentrated solution this way?
No. You need a stronger stock or a different process; dilution alone cannot increase concentration.
References & reading
- OpenStax, Rice University — Molarity ↗
Defines molarity and derives the dilution balance from conservation of solute.
- NIST — Guide to SI conversion factors ↗
Supports physical unit conversions. Input values are converted to the formula’s base units before calculation.
Our explanations are written for ChemistryCalc. Read how we build and check our tools. These calculations are educational estimates where the underlying model requires assumptions.