Molarity Calculator – Molar Concentration

Calculate molarity (M), moles, or volume for any solution.

Moles of solute (mol)

Volume of solution (L)

About This Calculator

Calculate molarity (M), moles, or volume for any solution. Use the calculator above for instant results.

Worked Examples

Example 1: 0.5 mol NaCl, 1L water

Molarity = 0.5/1 = 0.5 M

Answer: 0.5 M

Example 2: 0.1 mol HCl, 250mL (0.25L)

Molarity = 0.1/0.25 = 0.4 M

Answer: 0.4 M

Example 3: 2 mol glucose, 2L solution

Molarity = 2/2 = 1.0 M

Answer: 1.0 M

Who Uses This Calculator?

🧪

Chemistry Students

Calculate solution molarity.

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Lab Scientists

Prepare solutions at target concentration.

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Chemistry Teachers

Demo solution preparation.

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Pharmacists

Drug concentration calculations.

Common Mistakes to Avoid

❌ Dissolving in volume of water vs to volume

Molarity is based on total solution volume, not solvent volume. Dissolve solute, THEN add water to reach the final volume.

❌ Moles vs grams

Convert grams to moles using molar mass (g/mol). Moles = mass (g) / molar mass (g/mol). Find molar mass on the periodic table.

Frequently Asked Questions

Molarity formula?

M = n/V. Where n = moles of solute, V = volume of solution in liters.

Molarity vs molality?

Molarity: moles/liter of solution. Molality: moles/kg of SOLVENT. Molality used for colligative properties.

How to prepare 1L of 0.1 M NaCl?

Moles needed = 0.1 × 1 = 0.1 mol. Molar mass NaCl = 58.44 g/mol. Weigh 5.844g NaCl, dissolve in water, dilute to exactly 1L.