Molarity (M) is the number of moles of solute per liter of solution. It is the most common way to express concentration in chemistry.

What is the molarity formula?

M = n/V (moles per liter), or equivalently M = m/(MW × V) where m is mass in grams, MW is molecular weight, and V is volume in liters.

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Molarity Calculator

Q: What is a 1M solution?

A 1M solution contains 1 mole of solute dissolved in enough solvent to make exactly 1 liter of solution.

Q: How do I dilute a solution?

Use the formula M₁V₁ = M₂V₂. Multiply initial molarity by initial volume to find the amount of stock solution needed.

Solve For

Molarity (M = m / (MW × V))

Mass of Solute (grams)

Molecular Weight (g/mol)

Volume of Solution (liters)

Common Compounds - Molecular Weights

Compound	Formula	MW (g/mol)
Sodium Chloride	NaCl	58.44
Water	H₂O	18.015
Sulfuric Acid	H₂SO₄	98.079
Hydrochloric Acid	HCl	36.461
Sodium Hydroxide	NaOH	39.997
Glucose	C₆H₁₂O₆	180.156
Potassium Nitrate	KNO₃	101.103
Calcium Carbonate	CaCO₃	100.086

Molarity Calculator: Compute Molar Concentration Instantly

Our Molarity Calculator helps you calculate the molar concentration of a solution using mass, molecular weight, and volume. Whether you're preparing lab solutions, studying chemistry, or working in pharmaceuticals, this tool simplifies the math behind solution preparation.

Molarity (M) is one of the most common ways to express the concentration of a solute in a solution. It is defined as the number of moles of solute per liter of solution, measured in mol/L. Understanding molarity is essential for accurate chemical reactions and laboratory work.

This guide covers the molarity formula, practical examples, terminology disambiguation, and step-by-step instructions for preparing solutions of specific concentrations.

What is Molarity?

Molarity (M) is a measure of concentration defined as the number of moles of solute dissolved per liter of solution. It is the standard unit used in chemistry laboratories worldwide.

The formula is simple: M = n/V, where n is the number of moles and V is the volume in liters. When mass is known instead of moles, we can substitute: M = m / (MW × V), where m is mass in grams and MW is the molecular weight in g/mol.

Molarity is distinct from molality (moles per kg of solvent), normality (equivalents per liter), and mole fraction. Each has specific use cases in different areas of chemistry.

How to Use the Molarity Calculator

Step 1: Enter Mass: Input the mass of your solute in grams.
Step 2: Enter Molecular Weight: Input the molecular weight (molar mass) of the compound in g/mol.
Step 3: Enter Volume: Input the total volume of the solution in liters.
Step 4: Calculate: The fourth value (molarity) is calculated automatically. You can also leave any one field blank to solve for it.

Molarity Formulas

Basic Molarity

M = n / V

Moles of solute (n) divided by volume of solution (V) in liters.

Using Mass

M = m / (MW × V)

Mass (m) in grams divided by (molecular weight × volume in liters).

Finding Mass

m = M × MW × V

Multiply molarity × molecular weight × volume to find the required mass of solute.

Example Molarity Calculations

Solute	Mass (g)	MW (g/mol)	Volume (L)	Molarity (M)
NaCl	58.44	58.44	1	1.0 M
NaCl	10	58.44	0.5	0.342 M
KNO₃	202.2	101.1	2	1.0 M
HCl	36.46	36.46	1	1.0 M

Benefits of Our Molarity Calculator

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Solve for any variable: mass, molecular weight, volume, or concentration.
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Perfect for preparing stock solutions, dilutions, and titration calculations.
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Includes examples and explanations ideal for chemistry students.
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