Use this to calculate single-solute setup or multi-solute recipes for buffers, media, stocks, and routine lab solutions.
Useful Checks
Use this with the Dilution Calculator when a prepared stock solution needs to be diluted or converted to a final working concentration.
Multi-solute mode builds buffer, media, or stock recipes with several components in one calculation.
Multi-solute mode is especially useful for buffer, media, stain, and assay recipes because units, molecular weights, and stock multipliers stay together in one table.
For stock multipliers, enter the intended 1x working targets. If you choose 5x, 10x, 20x, or a custom multiplier, the result keeps the 1x amount visible beside the stock amount so manual multiplication errors are easier to catch.
Components can use molar units, % w/v, % v/v, mg/mL, µg/mL, or g/L, with molecular weight requested only where it is needed.
Minimum Inputs Needed
For single solute: concentration, molecular weight or selected compound, and final volume.
For % w/v: percent and final volume.
For multi-solute: recipe volume and at least one component.
Optional Settings
Tool mode
Choose single-solute for one compound. Choose multi-solute for a buffer or recipe.
Calculation mode
Choose whether the target is molarity or % w/v.
Stock multiplier
Use this only when preparing a concentrated stock such as 5x, 10x, or 20x. At 1x, the tool shows only the working-solution amount. Above 1x, it shows both the 1x working amount and the stock amount.
Compound search (optional)
Search common compounds to fill molecular weight automatically.
Molecular weight
Needed for molar calculations if you do not select a compound.
Preferred mass unit
Choose the unit used to display the mass. Auto is usually suitable.
Component unit
For multi-solute recipes, choose the unit for each component: molar, % w/v, % v/v, mg/mL, µg/mL, or g/L.
How To Use: Single Solute
Choose single-solute mode.
Choose molarity or % w/v.
Enter the working concentration and final volume.
Select a compound or enter molecular weight for molar calculations.
Choose a stock multiplier only if making a concentrated stock.
Click Calculate.
How To Use: Multi-Solute Recipe
Choose multi-solute recipe builder.
Enter the final recipe volume.
Choose 1x, 5x, 10x, or a custom stock multiplier.
Add each component and enter its 1x target.
Choose the unit for each component: molar, % w/v, % v/v, mg/mL, µg/mL, or g/L.
Enter molecular weight only for components using molar units, unless you select a compound from search.
Click Calculate.
Understanding The Results
The quick result shows the amount to weigh or add.
At 1x, the result shows only the amount for the final working solution.
For stock multipliers above 1x, the quick result and detailed table show both the 1x working amount and the selected stock amount.
In multi-solute stock mode, each row keeps the 1x target beside the stock target and amount to add.
The final step tells you to bring the complete mixture to the final recipe volume, not to add that much water on top.
Warnings may appear for very small masses, high concentrations, high % v/v totals, or solubility concerns.
Compound values are reference values from a curated offline list. Verify the exact reagent form you use.
Solubility warnings are approximate.
% w/v means grams per 100 mL final solution.
% v/v is a volume-to-add calculation, not a mass calculation.
For multi-solute stock recipes, component targets are treated as 1x working targets and multiplied for the stock recipe.
Examples
Single solute: To make 100 mL of 10 mM Tris, search Tris or enter the molecular weight, set 10 mM and 100 mL, then calculate the mass.
Multi-solute: To make a 5x buffer stock, enter the final stock volume, choose 5x, add each component at its 1x target, then prepare the listed 5x amounts and bring the mixture to the final volume.
Use note: These tools are for research and educational planning. Check important calculations and sequence designs before ordering reagents or running experiments.