Science & Engineering

Concentration (Molarity, Molality, % & ppm)

Compute molarity, molality, mass percent, and ppm from solute mass, molar mass, solvent mass, and solution volume. It includes a molar mass lookup for common compounds.

How to use

Enter the solute mass and its molar mass.
Add the solvent mass and solution volume as needed.
Pick the concentration unit you want to read.
Use the molar mass lookup for common compounds.

Solute

Solute mass (g)

Molar mass (g/mol)

Solvent mass (g)

Solution volume (mL)

Volume (mL)

Molarity

—

moles of solute per litre of solution

Molality (m)

—

Mass percent (w/w)

—

Parts per million

—

Moles of solute

—

For study and estimation. Verify against authoritative data before relying on a result.

Was this helpful?

Common questions

What is the difference between molarity and molality?

Molarity is moles of solute per liter of solution, while molality is moles per kilogram of solvent. Molality does not change with temperature.

How do I convert mass percent to ppm?

Multiply mass percent by 10,000. So 0.5% by mass equals 5,000 ppm.