Stock Solution and Antibody Dilution Calculator Help
Use this free online stock solution and antibody dilution calculator for C1V1, 1:N ratios, and stock-to-target concentrations.
Useful Checks
If the stock volume is too small to pipette directly, the result can flag the problem and point you toward an intermediate dilution.
Use this with the Molarity Calculator when you first prepare a stock solution and then need a working dilution.
The calculator handles normal C1V1 dilution and compatible unit conversions in the same calculation.
Antibody mode accepts either a direct 1:N dilution or stock and target antibody concentrations.
It can convert between molar units and mass or percent units when molecular weight is known, and asks for molecular weight only when that conversion needs it.
The result keeps stock volume, diluent volume, and final volume separate, with practical display units for small and large volumes.
Minimum Inputs Needed
For stock solutions, enter stock concentration, desired final concentration, and final volume.
For antibodies, enter a 1:N ratio or stock and target concentrations, plus final volume.
Optional Settings
Molecular weight required
Only needed when converting between molar units and mass or % w/v units.
Antibody calculation
Choose Dilution ratio (1:N) when a protocol gives a ratio, or Stock and target concentration for an antibody C1V1 calculation.
Available stock volume (optional)
Checks whether you have enough stock for the requested dilution.
Stock label (optional)
Adds a name to the result, useful when working with many stocks.
Concentration and volume units
Choose units that match your stock and final solution.
How To Use: Stock Dilution
Select Stock dilution.
Enter stock concentration, desired final concentration, and final volume.
Choose units that describe each value. Add molecular weight only if a molar-to-mass or molar-to-% w/v conversion requests it.
Optionally enter available stock volume and a stock label.
Click Calculate dilution. Later input changes update the result automatically.
How To Use: Antibody Dilution
Select Antibody dilution.
Choose Dilution ratio (1:N) or Stock and target concentration.
Enter the ratio or antibody concentrations.
Enter the desired final volume.
Click Calculate antibody dilution. Later input changes update the result automatically.
Understanding The Results
The quick result shows how much stock to take.
It also shows how much diluent to add.
The final volume is the total volume after stock plus diluent.
If the stock volume is very small, the tool may suggest an intermediate dilution.
Antibody or stock volumes below 1 µL are flagged with a practical intermediate-dilution recipe when possible.
The intermediate recipe separates preparation of the diluted intermediate stock from preparation of the final working solution.
If available stock is entered, the tool warns when it is insufficient and reports the maximum final volume that can be prepared.
Accepted Input Formats
Concentration units include M, mM, µM, nM, mg/mL, µg/mL, ng/µL, ng/mL, X, and % w/v.
Volume units include L, mL, µL, and nL.
Antibody concentration units include mg/mL, µg/mL, ng/mL, and µg/µL.
X dilutions work with X units only.
Assumptions And Limitations
The calculation assumes ideal dilution.
It does not account for density or volume contraction after mixing.
A 1:N antibody ratio means one volume of antibody stock in N total volumes, not one volume plus N volumes of diluent.
Antibody concentration mode is a C1V1 calculation and does not account for binding activity, purity, carrier protein, or assay-specific performance.
Very small volumes should be handled with appropriate pipettes or intermediate dilution.
Examples
To dilute 10 mM stock to 1 mM in 100 µL final volume, enter 10 mM, 1 mM, and 100 µL. The result is 10 µL stock plus 90 µL diluent.
For a 1:1000 antibody dilution in 500 µL final volume, choose Dilution ratio (1:N) and enter 1000. The direct recipe is 0.5 µL antibody plus 499.5 µL diluent, so the tool also flags the low volume and provides an intermediate-dilution option.
Use note: These tools are for research and educational planning. Check important calculations and sequence designs before ordering reagents or running experiments.