Tools HubDilution Calculator
Find the required stock volume from stock concentration, target concentration and final solution volume using C₁V₁ = C₂V₂.
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Result
Worked steps
Approximate results are displayed to at most 10 significant digits. Measurement significant figures and uncertainty are not inferred.
Formula and example
If the amount of solute stays constant, C₁V₁ = C₂V₂. Use stock concentration C₁, target concentration C₂ and final volume V₂ to find the required stock volume V₁ = C₂V₂ / C₁.
C₁V₁ = C₂V₂ → V₁ = C₂V₂ / C₁
C₁ = 1 mol/L, C₂ = 0.1 mol/L, V₂ = 100 mL → V₁ = 10 mL
- Tenfold dilution1 mol/L → 0.1 mol/L, final 100 mL → stock 10 mL
- Fivefold dilution0.5 mol/L → 0.1 mol/L, final 250 mL → stock 50 mL
- Use mmol/L100 mmol/L → 25 mmol/L, final 40 mL → stock 10 mL
Common mistakes
- Use the same concentration unit for stock and target. The unit selector applies to both.
- Do not confuse final solution volume with solvent added. This tool does not assume additive volumes or calculate solvent volume.
Check the assumptions
Assumes the amount of solute is unchanged. Concentrations and volume must be positive, and the target cannot exceed the stock. Final volume means total diluted solution volume, not the volume of solvent added.
Calculations run in your browser. Inputs and results are not sent or saved.
OpenStax · Chemistry 2e — Molarity and Dilution ↗How to use
- 1
Enter values and units
Use the example or enter your own conditions.
- 2
Calculate
Check the result and each calculation step.
- 3
Check assumptions
Review applicability and display precision, then copy inputs and results if needed.
Features
- Worked steps and unit conversions
- No account; calculation stays in your browser
- Copy inputs and results together
Use cases
Check your working
Compare formula substitutions and units with your own calculations.
Details
Assumes the amount of solute is unchanged. Concentrations and volume must be positive, and the target cannot exceed the stock. Final volume means total diluted solution volume, not the volume of solvent added.
FAQ
How is the dilution factor calculated?
Divide stock concentration by target concentration. Diluting 1 mol/L to 0.1 mol/L is a tenfold dilution.
Can the target be more concentrated than the stock?
No. Adding solvent cannot increase concentration. The target must be no higher than the stock concentration.
Are results exact?
Results use floating-point approximations, displayed to at most 10 significant digits. Measurement significant figures and uncertainty are not inferred.
Are inputs saved?
Inputs and results are not sent to a server or saved. They disappear when you leave the page.
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