Molecular Weight Calculator - Calculator See


Molecular Weight Calculator

Calculate the molar mass (molecular weight in g/mol) and mass percentage elemental composition from chemical formulas (e.g. H2O, C6H12O6, NaCl).

Calculator Inputs

Enter chemical formula (e.g. H2O, NaCl, C6H12O6, H2SO4, CaCO3).

Calculated Results

Calculated Molar Mass
180.16 g/mol (Glucose - C6H12O6)
Carbon Mass % 40.00% (72.06 g/mol)
Oxygen Mass % 53.28% (96.00 g/mol)
Hydrogen Mass % 6.72% (12.10 g/mol)
Values calculate live as you adjust inputs.

About Molecular Weight Calculator

Parses chemical formulas and sums standard atomic weights of constituent elements from the periodic table to compute total molecular mass.

What is Molecular Weight Calculator?

Parses chemical formulas and sums standard atomic weights of constituent elements from the periodic table to compute total molecular mass.

How to Use This Calculator

  1. Type chemical formula using standard case-sensitive element symbols (e.g. NaCl, C6H12O6).
  2. Read molecular weight in g/mol and elemental mass percentages.

The Mathematical Formula & Variables

Molecular Weight = Sum of (Atom Count * Atomic Weight for each element)

Step-by-Step Worked Example

Scenario: Glucose (C6H12O6).

  1. Carbon: 6 * 12.011 = 72.066 g/mol.
  2. Hydrogen: 12 * 1.008 = 12.096 g/mol.
  3. Oxygen: 6 * 15.999 = 95.994 g/mol.
  4. Total MW = 72.066 + 12.096 + 95.994 = 180.16 g/mol.

Result: 180.16 g/mol

Frequently Asked Questions

What are the units of molar mass?

Molar mass is expressed in grams per mole (g/mol) or unified atomic mass units (u / Daltons).