Molecular Weight Calculator

Molar mass in g/mol from a chemical formula like H2O, Ca(OH)2 or CuSO4·5H2O.

Molecular Weight Calculator helps you molar mass in g/mol from a chemical formula like H2O, Ca(OH)2 or CuSO4·5H2O. Enter formula, review the breakdown, and use the guidance below to understand what the number means — and what it does not. What the Molecular Weight calculator does Molecular Weight Calculator is built for arithmetic, algebra, geometry, and number tools. Molar mass in g/mol from a chemical formula like H2O, Ca(OH)2 or CuSO4·5H2O. You enter formula, then Simple Calculators computes the result instantly. Results use standard school and engineering formulas that run privately in your browser. How the math works Type the Formula, such as H2O or NaCl, with a capital letter starting each element and the number of atoms after it. Brackets multiply everything inside them — Ca(OH)2 counts two oxygens and two hydrogens — and a dot adds water of crystallisation, as in CuSO4·5H2O. For each element the calculator multiplies the number of atoms by its standard atomic weight, then adds them up. The formula: Molecular weight = total of (number of atoms × atomic mass) for each element. Atomic masses come from the periodic table, in grams per mole (g/mol).