CalculatorHand-checked fixturesFull working shown
Molar Mass Calculator
Compute the molar mass of any compound from its formula — with per-element contributions, mass percentages, and the data source shown.
Calculator
Results update as you type. Every step of the working is shown below.
Examples:
Result
Enter values above — the answer appears here instantly, with full working.
Formula used
M = Σ(nᵢ · Aᵢ)
Every result substitutes your values into this relation step by step above.
Assumptions
- Standard atomic weights (CIAAW 2021 conventional values) — natural isotopic mixtures.
- The formula describes one well-defined compound.
Limitations
- Elements without stable isotopes use the longest-lived isotope mass number — flagged in the result.