Chemistry

Dilution Calculator (C1V1 = C2V2)

How much stock solution do you need to make a diluted solution?

Your numbers

Your results

Stock needed, V₁ (mL)
Stock needed, V₁ (mL)
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Diluent to add (mL)
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Dilution factor
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Dilution Calculator (C1V1 = C2V2) by TheCalcTools

How the Dilution Calculator (C1V1 = C2V2) works

Enter the stock concentration, the concentration you want and the final volume.

The amount of solute is unchanged by dilution, so C₁V₁ = C₂V₂.

Add the stock to a container, then top up with diluent to the final volume.

The formula

C₁ V₁ = C₂ V₂V₁ = C₂ V₂ ÷ C₁

Worked example

Using the default values shown in the calculator:

Stock concentration C₁12
Target concentration C₂1
Final volume V₂ (mL)500
  1. V₁ = 1 × 500 ÷ 12 = 41.67 mL of 12 M stock.
  2. Add 458.33 mL of diluent to reach 500 mL.
  3. The dilution factor is 12×.

Result:

Stock needed, V₁ (mL)41.667
Diluent to add (mL)458.333
Dilution factor12.000

Frequently asked questions

Do the units matter?

C₁ and C₂ can be in any unit as long as they match (mol/L, %, ppm). V₁ and V₂ must also match.

Should I add water to acid or acid to water?

Add concentrated acid slowly to water, never the reverse, because the heat released can cause spattering. Follow your lab’s safety rules.

Sources and further reading

More in Chemistry · All calculators

This calculator gives estimates for information only. Check important results independently before you rely on them. See our disclaimer.