Dilution calculator
Make a weaker solution: enter the strength you have, the strength you want, and how much finished solution you need.
Result
Calculate to see the result.
- Water / solvent to add (approx.)
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- Dilution factor per step
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- Final concentration
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General education only. Not for medication dosing or hazardous mixing.
| Step | Concentration |
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How to use
- Original concentration: A.
- Desired concentration / Desired total volume: C.
- Amount of original solution to use: A. B · Add water: B.
Worked example
To make 100 mL at 1% (1 g per 100 mL) from a 10% stock, use 10 mL of stock and dilute to a final 100 mL. The nominal water/solvent difference is 90 mL.
Limits and interpretation
The equation conserves solute without reaction or loss. V₂ is the final solution volume, not the solvent volume. V₂ − V₁ assumes additive volumes and is a nominal estimate; real mixtures may contract or expand. This is a mathematical guide, not a preparation procedure. % w/v means grams per 100 mL; % v/v means volume per 100 volumes. Mass percent (% w/w) and density-based conversions are not supported.
Frequently asked questions
What volume remains in a serial dilution?
Each step reaches V₂ before the next transfer. Removing V₁ for the next step leaves V₂ − V₁ in that vessel. Only the last vessel retains all V₂. The table lists concentrations, not guaranteed collected volumes.
Can I calculate a stronger solution?
No. Dilution cannot raise concentration. Equal stock and target concentrations are accepted and give factor 1 with zero nominal solvent.
Why reject mixed concentration families?
For example, converting M to g/L requires the solute’s molar mass. This calculator does not guess it. Within a compatible family it converts units before applying the equation.