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Molecular Weight Calculator
Calculate the breakdown of molar mass for any chemical formula instantly.
Molecular Weight Calculator
Calculate molar mass from chemical formula.
Case sensitive (e.g. Co vs CO). No parentheses.
Understanding the Molecular Weight & Molar Mass Calculator
Calculate the molecular weight (molar mass) of any chemical compound by entering its formula. Our tool breaks down the contribution of each element and provides a visual mass distribution chart.
How to use the Molecular Weight & Molar Mass Calculator
- 1Enter the chemical formula (e.g., H2O, C6H12O6) in the input field.
- 2Ensure correct capitalization: the tool treats 'Co' as Cobalt and 'CO' as Carbon Monoxide.
- 3Click 'Calculate Mass' to see the result in grams per mole (g/mol).
- 4Review the pie chart to see which elements contribute the most to the total weight.
Common Use Cases
The Maths Behind the Calculation
MW = Σ (AtomicWeight_i × Count_i)Molecular Weight (MW) is the sum of the atomic weights of all atoms in a molecule. For example, H2O consists of 2 atoms of Hydrogen (1.008 each) and 1 atom of Oxygen (15.999).
Frequently Asked Questions
What is the difference between Molecular Weight and Molar Mass?
While often used interchangeably, molecular weight is the mass of a single molecule (in amu), whereas molar mass is the mass of one mole of those molecules (in g/mol).
Why is capitalization important?
In chemistry, symbols start with a capital letter. 'Na' is Sodium, but 'na' would be invalid. 'CO' is Carbon and Oxygen, while 'Co' is Cobalt.
Are parentheses supported?
In this version, parentheses are not supported. Please expand your formula (e.g., use MgN2O6 instead of Mg(NO3)2).
Regional Notice: United States
"Federal tax estimates are based on 2024 brackets. Consult a tax professional for official filing."