Molecular Weight Calculator

What is Molecular Weight?

Molecular weight, also known as molar mass, is the sum of the atomic masses of all atoms in a molecule. It is expressed in grams per mole (g/mol). This value is essential for a variety of applications in chemistry, biology, and engineering. Understanding the molecular weight of compounds is a crucial part of chemistry, helping researchers and students alike in various calculations, from stoichiometry to solution preparation. Use our Molecular Weight Calculator to quickly and accurately determine the molecular weight of any compound by simply entering its molecular formula.For example:

The molecular weight of H2O (water) is calculated as:
2×H (1.008 g/mol)+1O (15.999 g/mol)=18.015g/mol.

Why is Molecular Weight Important?

Molecular weight has practical applications across many scientific disciplines:

Chemical Reactions:
Knowing molecular weights helps determine the exact amount of reactants needed for a reaction, ensuring balanced equations and proper stoichiometry.
Solution Preparation:
It aids in preparing accurate concentrations for solutions in molarity calculations.
Pharmaceuticals and Biochemistry:
Molecular weight is critical for understanding biomolecules like DNA, proteins, and drug molecules.
Environmental Studies:
Molecular weights are used to calculate emissions and analyze pollutants.

How to Use the Molecular Weight Calculator

Enter the Molecular Formula:
Type the formula of the compound (e.g., H2O, CO2, C6H12O6) in the input box.
Click on “Calculate”:
Press the Calculate Molecular Weight button to process your input.
View the Result:
The calculator will display the molecular weight in grams per mole (g/mol).

Common Examples of Molecular Weight Calculations

Water (H2O): 2×1.008(H)+15.999(O)=18.015g/mol.
Carbon Dioxide (CO2): 1×12.011(C)+2×15.999(O)=44.009g/mol.
Glucose (C6H12O6): 6×12.011(C)+12×1.008(H)+6×15.999(O)=180.156g/mol.

Molecular Weight Calculator

Enter Molecular Formula: