How It Works
This calculator works in 4 steps.
Enter the stock molarity
Type the concentration in M, mM, µM, or nM.
Enter the target molarity
Type the working concentration; prefixes may differ from the stock.
Enter the final volume
Type the volume in L, mL, or µL.
Read the stock volume and moles
The calculator converts both concentrations to M, solves V₁ = M₂V₂ / M₁, and reports the moles of solute transferred.
The Formula
The formula sets the moles in the stock aliquot equal to the moles in the final solution.
M₁ × V₁ = M₂ × V₂n = M₂ × V₂1 M = 10³ mM = 10⁶ µM = 10⁹ nM- M₁:
- Stock molarity (mol/L)
- M₂:
- Target molarity
- V₁ / V₂:
- Stock and final volumes
- n:
- Moles of solute
To make 500 mL of 1 M HCl from 6 M HCl, V₁ = 1 × 500 / 6 = 83.3 mL. The solution contains 0.5 mol (500 mmol) HCl.
Conversion Table
The conversion table lists stock volumes and moles transferred for 6 molar dilutions.
| Stock | Target | Final volume | Stock volume | Solute amount |
|---|---|---|---|---|
| 1 M | 0.1 M (100 mM) | 100 mL | 10 mL | 10 mmol |
| 6 M | 1 M (1,000 mM) | 500 mL | 83.33 mL | 500 mmol |
| 12.1 M | 0.5 M (500 mM) | 250 mL | 10.33 mL | 125 mmol |
| 0.5 M | 0.05 M (50 mM) | 1,000 mL | 100 mL | 50 mmol |
| 5 M | 0.15 M (150 mM) | 200 mL | 6 mL | 30 mmol |
| 2 M | 0.002 M (2 mM) | 50 mL | 0.05 mL | 0.1 mmol |
What Is the Molarity Dilution Calculator?
The Molarity Dilution Calculator is a tool that dilutes solutions expressed in moles per liter (mol/L, M) and returns the stock volume, diluent volume, and moles of solute transferred. The calculator accepts M, mM, µM, nM, and pM on either side and converts the prefixes before solving.
Molarity counts solute particles, so molar dilution keeps reaction stoichiometry visible. The number of moles in the stock aliquot equals the number of moles in the final solution: n = C × V. The calculator shows this mole count in mmol or µmol, so the user can match it with a reaction recipe.
Common Uses
There are 5 main uses of this calculator.
Acid and base preparation
Chemists dilute concentrated HCl, H₂SO₄, and NaOH to working molarity.
Titrant preparation
Analysts prepare 0.1 M and 0.01 M titrants from 1 M stocks.
Salt solutions
Biologists make 150 mM NaCl from 5 M NaCl stock.
Reaction setup
Researchers deliver an exact mole amount to a reaction vessel.
Stoichiometry teaching
Instructors link dilution to mole counting in general chemistry.