Molecular Weight Calculator

Calculate molecular weight from a chemical formula. Get an elemental breakdown and instant results.

Molecular Weight Tips

What is Molecular Weight?

Molecular weight (molar mass) is the sum of atomic weights of all atoms in a molecule. Unit: g/mol.

How to Calculate

Add up (count × atomic weight) for each element in the formula. Example: H2O = 2×1.008 + 1×15.999 = 18.015 g/mol.

Examples

CO2: 44.009 g/mol. Glucose (C6H12O6): 180.156 g/mol.