Molecular Weight Calculator
Calculate the molar mass of any chemical formula with an element breakdown.
Enter your values to see the result.
Continue your work
- Scientific Calculator — Do further calculations.
- Weight Converter — Convert between mass units.
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Clear instructions
Find steps, examples and limitations below.
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How to use the Molecular Weight Calculator
Calculate the molar mass of any chemical formula with an element breakdown.
- 1 Enter a chemical formula such as C6H12O6 or CuSO4·5H2O. Capitalization matters.
- 2 Read the molar mass and composition by element.
- 3 Optionally enter a mass in grams to convert it to moles and molecules.
Example and practical tips
Glucose, C6H12O6, has a molar mass of about 180.16 g/mol, so 90 g is 0.5 mol.
Frequently asked questions
Why does capitalization matter?
Element symbols start with a capital letter: Co is cobalt, while CO is carbon monoxide.
Which atomic weights are used?
Standard atomic weights from IUPAC, rounded to about four or five significant figures.
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