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Molar Mass Calculator

Calculate the molar mass of a chemical compound. Enter the molecular formula (e.g. H₂SO₄) and get the molar mass with element composition.

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The molar mass calculator computes the molar mass (also called molecular weight) of a chemical compound from its molecular formula. The molar mass indicates the mass of one mole of a substance in grams and is expressed in g/mol.

The calculation is based on standardized atomic masses from IUPAC (International Union of Pure and Applied Chemistry). Each element in the formula is multiplied by its atomic mass and all contributions are summed. The calculator also supports complex formulas with parentheses like Ca(OH)₂ or Fe₂(SO₄)₃.

The molar mass is a fundamental quantity in chemistry. It is needed for stoichiometric calculations, preparing solutions of defined concentration, and converting between mass and amount of substance.

Frequently Asked Questions

What is molar mass and how is it determined?
Molar mass is the mass of one mole of a substance in g/mol. It is determined by adding up the atomic masses of all atoms in the molecular formula. For water (H₂O): 2 × 1.008 (H) + 15.999 (O) = 18.015 g/mol.
Which chemical formulas are supported?
The calculator supports simple formulas like NaCl or H₂SO₄ as well as complex formulas with parentheses like Ca(OH)₂, Fe₂(SO₄)₃, or Mg₃(PO₄)₂. Enter the formula using uppercase letters for elements and numbers for the count.
Why do I need the molar mass?
The molar mass is needed for many chemical calculations: converting grams to moles (and vice versa), preparing solutions of specific molarity, stoichiometric calculations in chemical reactions, and determining the percentage element composition.

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