Molar Mass Calculator
Find the molar mass of any compound from its formula and see the mass of each element. The result updates as you type, with the working underneath so you can check it.
Your details
Result
Molar mass
74.092 g/mol
Composition by element
| Element | Atoms | Atomic mass | Mass in formula | Mass % |
|---|---|---|---|---|
| Ca | 1 | 40.078 | 40.078 | 54.09% |
| O | 2 | 15.999 | 31.998 | 43.19% |
| H | 2 | 1.008 | 2.016 | 2.72% |
- Uses IUPAC standard atomic weights. Values are rounded to the precision most textbooks use.
Good to know: M = Σ (atomic mass × number of atoms)
Please note: For study and planning. Check calculations independently before using results with chemicals, electricity, pressure or machinery, and follow safety data sheets, manufacturer instructions and local regulations.
About this tool
Formula
M = Σ (atomic mass × number of atoms)
Questions people ask
How do I calculate molar mass?
Add the atomic mass of every atom in the formula. For water, H₂O: 2 × 1.008 + 15.999 = 18.015 g/mol. Brackets multiply everything inside them, and a hydrate dot such as CuSO₄·5H₂O adds the water.
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- PPM CalculatorConvert between parts per million, mg/L and percent.
How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
Spotted a mistake? Tell us and we'll check it. How we check our calculators