Molarity Calculator – Calculate molarity from moles and volume.
Molarity (M) expresses concentration as moles of solute per liter of solution. This free online molarity calculator instantly determines the concentration of chemical solutions for laboratory, academic, and industrial use. Supports mol (moles), mmol (millimoles), liters (L), and milliliters (mL).
Whether you are preparing a solution for a chemistry experiment, performing a titration, or calculating dilution ratios, our tool helps you get accurate results fast. Simply enter the number of moles (or mmol) of the solute and the final volume of the solution, and the calculator will output the molarity in mol/L. Perfect for chemistry students, teachers, researchers, and lab technicians.
Includes step-by-step molarity formula, example problems, and common FAQs to improve your understanding of concentration calculations.
Calculate Your Molarity
Tip: 1 mol = 1000 mmol
1 L = 1000 mL
Molarity Formula
Molarity (M) is moles of solute per liter of solution.
M = n / V
- n = moles of solute (mol)
- V = volume of solution (L)
Dissolve 0.50 mol of NaCl and make the solution up to 0.25 L.
M = 0.50 / 0.25 = 2.0 M
The solution is 2.0 molar (2.0 mol·L⁻¹).
What is Molarity?
Molarity is a common concentration unit in chemistry that tells you how many moles of solute are present per liter of solution. It’s widely used for reaction stoichiometry, titrations, and preparing standard solutions in labs.
1 M = 1 mol per liter (mol·L⁻¹). 1 L = 1000 mL; 1 mol = 1000 mmol.
Use total solution volume, not just solvent volume. Temperature can slightly change volume.
Try Dilution, Normality, pH/pOH, Buffer, and Titration calculators for full lab workflows.
Where is Molarity Used?
Molarity is essential in both academic and professional chemistry for tasks that require precise concentration measurements. Here are some common applications:
- Laboratory Experiments: Preparing standard solutions for chemical reactions and analysis.
- Titrations: Determining the concentration of an unknown solution using a known standard.
- Pharmaceuticals: Ensuring correct dosages and solution strengths in drug preparation.
- Water Treatment: Calculating the amount of chemicals needed for purification processes.
- Industrial Chemistry: Controlling concentrations in manufacturing processes like food, cosmetics, and cleaning products.
- Environmental Testing: Measuring pollutant concentrations in soil and water samples.
FAQs
Is molarity the same as molality?⌄
No. Molarity is moles per liter of solution (volume-based), while molality is moles per kilogram of solvent (mass-based).
Should I use solution volume or solvent volume?⌄
Always use the final solution volume. After dissolving the solute, adjust the total volume to the mark.
Why does temperature matter?⌄
Volume changes with temperature. Since molarity uses volume, concentration can vary slightly as temperature changes.
How do I prepare a 1.0 M solution?⌄
Dissolve 1.0 mol of solute in a volumetric flask and add solvent to reach exactly 1.0 L of solution.