How to Use
- Enter initial concentration
Input the starting concentration (C1) and volume (V1) of your solution.
- Set target
Enter the desired final concentration (C2) or final volume (V2).
- View results
Click Calculate to see the required solute volume and diluent amount.
What Is Dilution?
Dilution is the process of adding solvent (usually distilled water) to a concentrated solution to lower its concentration, that is, the amount of solute per unit volume. The key point is that even when you add solvent, the absolute amount of solute does not change. Only the total volume increases, so the same amount of solute spreads over a larger space and the concentration drops.
Where is it used?
- Laboratories: preparing a working solution of the desired concentration from a stock solution
- Medicine and clinical settings: adjusting injectables and reagents to a prescribed concentration
- Chemical and environmental analysis: stepwise dilution when a sample is too concentrated and falls outside the measurement range
Enter any three of initial concentration (C1), initial volume (V1), final concentration (C2), and final volume (V2), and this calculator automatically solves for the remaining one and even tells you how much additional solvent to add.
Calculation Formula
The basic principle of dilution is C1 × V1 = C2 × V2. Since both sides represent the 'amount of solute', this value is conserved before and after dilution.
- C1: initial (pre-dilution) concentration
- V1: initial volume = amount of stock solution used
- C2: final (post-dilution) concentration
- V2: final volume
Worked Example
If you want to make a 2M solution from a 10M stock and use 50mL of stock, the final volume is V2 = C1 × V1 / C2 = 10 × 50 / 2 = 250mL. Therefore the solvent to add is V2 - V1 = 250 - 50 = 200mL. Note that the units must match between C1 and C2, and between V1 and V2.