Calculate dilution factor with a named convention
This dilution factor calculator defines DF as final volume divided by stock aliquot volume, which is equivalent to stock concentration divided by final concentration for an ideal simple dilution. Choose the pair of known values you have. The result always displays the convention, preventing confusion with sources that use the reciprocal or use “dilution” to mean a mixing ratio.
A 10 mL aliquot brought to 100 mL final volume has DF = 10 and requires 90 mL of diluent by arithmetic difference. A 1 mol/L stock diluted to 0.1 mol/L also has DF = 10. An undiluted sample has DF = 1; this convention never gives a factor below one for a valid dilution.
Use aliquot and final volume
In volume mode, enter the measured stock aliquot and final solution volume in the same unit. The calculator divides final volume by aliquot and subtracts aliquot from final volume to show diluent. Final volume cannot be smaller than aliquot because adding diluent cannot reduce total volume in this simple preparation model.
“Bring to 100 mL” means adjust the mixture until its total final volume is 100 mL, not necessarily add exactly 100 mL of diluent. The displayed diluent is the ideal arithmetic difference. For precision preparation, follow volumetric technique and account for any non-additive behaviour described by the method rather than treating the difference as an exact pouring instruction.
Use stock and final concentration
In concentration mode, enter stock and final values on exactly the same basis and unit. Dividing Cstock by Cfinal gives the factor because solute amount is conserved in the simple dilution relationship. A final concentration greater than stock is rejected; that would describe concentration, reaction, evaporation, or another process rather than dilution with blank solvent.
Percent, mol/L, mg/L, and ppm can each be used as a ratio only when both entries share that one definition. Do not divide a percent stock by an mg/L target or combine mass-based ppm with volume-based ppm. Convert to a common basis first when density, molar mass, or another relationship is properly known.
Verify factor and dilution series
Multiply final concentration by DF to recover stock concentration, or multiply aliquot volume by DF to recover final volume. These reverse checks should match within rounding. A larger final volume at fixed aliquot raises DF, while a lower final concentration at fixed stock also raises it. Both routes should agree when all four values describe the same preparation.
For serial dilutions, multiply the factor from each independent step to obtain the overall factor. Two successive tenfold dilutions give an overall factor of 100. Do not add the factors. Record each aliquot, final volume, and concentration basis so a large overall factor can be traced back and preparation errors are easier to locate.
Preparation limits and privacy
The calculation assumes solute is conserved and the chosen blank or solvent is appropriate. It does not check chemical compatibility, reaction, adsorption, degradation, instrument range, biological sterility, or product instructions. For medical, laboratory, or regulated preparations, follow the validated procedure and qualified supervision rather than relying on the factor alone.
The values are calculated in the current browser tab. NexaCurrent does not upload the quantities, formulas, chemical names, element choices, or other information entered here, and no account is needed. Copying is a deliberate action after the answer and working are visible. Refreshing or leaving the page clears the current calculation, so keep a copied result if it is needed for later study.