What is the dilution equation?

The dilution equation is C1 × V1 = C2 × V2, where C1 and V1 are the stock concentration and volume, and C2 and V2 are the final concentration and volume after dilution.

What units should I use?

Any units work as long as they match on both sides — use the same concentration unit (M, %, mg/mL) and the same volume unit (mL or L) throughout.

How much solvent do I add?

Solvent to add equals the final volume minus the stock volume (V2 − V1). The tool shows this automatically when you solve for a volume.

Dilution Calculator (C1V1 = C2V2)

Solve the dilution equation for any concentration or volume.

Dilution calculator

When you dilute a concentrated stock solution, the amount of solute stays the same, so C1 × V1 = C2 × V2. This relates the stock concentration and volume (C1, V1) to the diluted final concentration and volume (C2, V2).

Pick the unknown, enter the three values you know — keeping concentration and volume units consistent on both sides — and the calculator solves for the rest and tells you how much solvent to add. All in your browser, nothing uploaded.