Dilution calculator (C1V1 = C2V2)
Calculate solution dilutions with C1·V1 = C2·V2: enter three values to find the fourth, plus how much solvent to add. Works for mol/L, g/L, percent and ppm.
How to useDiluting solutions
Fill in three fields and leave blank the one you want to find.
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Dilution calculator (C1V1 = C2V2): what it is for
Enter three of the four values (initial concentration and volume, final concentration and volume) and the tool calculates the missing one with the formula C1·V1 = C2·V2. It also shows the volume of solvent to add and the dilution factor, and it works with any concentration unit, as long as it's the same at both ends.
The calculations run in your browser.
How to use
- Fill in three fields.
- Choose the units.
- See the calculated value and the solvent to add.
When to use it
- Prepare solutions in the lab.
- Dilute concentrated cleaning products.
- Solve chemistry exercises.
Frequently asked questions
How does the formula C1·V1 = C2·V2 work?
When diluting, you only add solvent, so the amount of solute doesn't change. Initial concentration times initial volume equals final concentration times final volume. Knowing three values, the tool calculates the fourth.
Which units can I use?
Any, as long as both concentrations are in the same unit (mol/L, g/L, %, ppm) and both volumes are too (mL or L).
Is the final volume the amount of water I add?
No. V2 is the total volume of the solution after diluting. The water to add is V2 minus V1, and the tool shows that value.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.