How this calculator works
Reconstitution dissolves a known dry mass to make a solution at a chosen concentration. Divide mass by the final solution volume, or rearrange for a missing quantity. One kg/m3 equals one mg/mL numerically. Solute can displace solvent volume, so the calculated volume is the final solution volume, not necessarily the diluent volume to add. This general chemistry tool does not choose a medicine dose, diluent, sterility method or stability period.
Formula
Mass concentration = solute mass / final solution volume. Final volume = solute mass / target mass concentration.
Worked example
Dissolving 1000 mg to a final 10 mL gives 100 mg/mL. To obtain 50 mg/mL from 2000 mg, make up to a final volume of 40 mL.
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Frequently asked questions
Is final volume the amount of diluent?
Not necessarily. A dissolved powder can change total volume.
Does this choose the right solvent?
No. Solubility, chemical compatibility and any product instructions determine solvent choice.
Can this calculate a patient dose?
No. It only balances mass and volume for a general solution.