Molar Mass Calculator

Compute the molar mass of any formula, including parentheses like Ca(OH)₂.

How the Math Works

The Molar Mass Calculator determines the total mass of one mole of a chemical compound by summing the atomic masses of each element multiplied by their respective counts in the formula. For example, in water (H2O), the calculation is (2 × hydrogen atomic mass) + (1 × oxygen atomic mass). Atomic masses are drawn from the periodic table, representing the average mass of all isotopes of each element in atomic mass units (amu). This gives the molar mass in grams per mole (g/mol), the mass needed for one mole of that substance.

Practical Applications

To use this calculator, simply enter any valid chemical formula such as NaCl, C6H12O6, or Fe2(SO4)3. The calculator automatically parses the formula, identifies each element and its count, retrieves the current atomic masses, and performs the summation. This is essential for preparing precise solutions in chemistry labs, converting between grams and moles in stoichiometric calculations, and verifying the correct proportions in chemical reactions.

Day-to-Day Use

Understanding molar mass helps you make informed decisions in everyday life involving chemicals. When mixing cleaning solutions, you can ensure correct concentrations by knowing the exact amount of active ingredients. Nutrition labels showing compound concentrations become more meaningful when you understand what those values represent at the molecular level. Even in cooking, knowledge of molecular weights helps explain why certain substances dissolve better or react differently in recipes.

Worked example

H2O → 18.015 g/mol; Ca(OH)2 → 74.09 g/mol.

FAQ