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Molarity Calculator

Find the mass, molarity or volume of a solution from the other two and your compound's molecular weight. Use it when making buffers, salt solutions and stock solutions from powders.

Choose what you want to find, then enter the other values and your compound's molecular weight. We'll work out how much to weigh, how concentrated your solution is, or how much to dissolve it in.

What do you want to find?

The concentration you want your solution to be.

The total volume of solution, after the compound is dissolved.

Also called formula weight. You'll find it on the reagent's label or datasheet, e.g. 58.44 for NaCl.

g/mol
Enter your values and press Calculate to see the mass needed.

How it's calculated

Mass (g) = molarity (mol/L) × volume (L) × molecular weight (g/mol)

Molarity (mol/L) = mass (g) ÷ (volume (L) × molecular weight (g/mol))

Volume (L) = mass (g) ÷ (molarity (mol/L) × molecular weight (g/mol))

Values are converted to grams, litres and mol/L before calculating, then shown in the units you chose. For a hydrated salt, use the molecular weight of the hydrate on the label.