Molar Mass Calculator

Enter a chemical formula to get its molar mass in g/mol and convert between grams and moles instantly.

Chemical Formula

Common Compounds

Gram / Mole Converter

Enter either Grams or Moles — the other updates automatically once a formula is set.

Results

Enter a chemical formula above.

Try H2O, NaCl, or Ca(OH)2.

Summary

Enter a chemical formula to get its molar mass in g/mol and convert between grams and moles instantly.

How it works

  1. Type a chemical formula such as H2O, NaCl, or C6H12O6 in the formula field.
  2. The parser reads each element symbol and subscript, handling parentheses like Ca(OH)2.
  3. Atomic masses from the IUPAC 2021 standard are looked up for each element.
  4. Each element contribution is summed to produce the total molar mass in g/mol.
  5. Optionally enter a mass (grams) or amount (moles) to convert between the two units.

Use cases

  • Chemistry students calculating molar mass for stoichiometry problems.
  • Lab technicians preparing solutions that require precise amounts of a compound.
  • Converting a measured mass of a reagent into the number of moles for a reaction.
  • Verifying formula weights when cross-checking published compound data.
  • Pharmaceutical and biochemistry work involving precise concentration calculations.
  • Teaching aid to illustrate how atomic masses contribute to compound mass.

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu