Molar mass calculator Chemistry

Molar mass of a substance

Calculation using a chemical formula with analysis of elements

Incorrect formula
Parentheses are supported, for example: Ca(NO3)2. Be case sensitive (NaCl, not nacl).
Enter the formula on the left
to calculate mass and composition
Molar mass:
0.00 g/mol
Composition (g/mol):

Molar mass calculator

🧪 Instant calculation of the molar mass of a substance

Molar mass (M) is a key parameter for the preparation of solutions and stoichiometric calculations. Our tool replaces the periodic table and calculator, doing all the routine work for you.

🚀 Main feature: We don’t just give the answer, but show a step-by-step solution. The calculator describes what makes up the final figure - this is ideal for students and schoolchildren when checking problems.

How does it work?

  1. Enter a formula: any elements, numbers and parentheses are supported (for example, Al2(SO4)3).
  2. Case is not important: you can write h2o or H2O - the system will understand.
  3. Get the result: exact weight in g/mol with details for each element.

For calculations we use the current atomic masses of elements according to the latest IUPAC standards.

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Angstrom🔬 Converter Angstrom (Å) ⇄ Nanometer (nm) In physics and chemistry you often have to switch between these units. Our tool does this instantly. ⚡ Quick cheat sheet: 1 Nanometer (nm) = 10 Angstrom (Å) 1 Angstrom (Å) = 0.

Examples that the calculator solves

Our algorithm can handle even complex compounds and organic chemistry:

💧 Water (H2O)
Simple calculation of the sum of hydrogen and oxygen atoms.
Result: ~18.015 g/mol
🍬 Glucose (C6H12O6)
Basic organics. Add 6 carbons, 12 hydrogens and 6 oxygens.
Result: ~180.156 g/mol
⚗️ Aluminum sulfate (Al2(SO4)3)
Complex formula with brackets. The calculator correctly multiplies the SO4 group by 3.
Result: ~342.132 g/mol

Frequently asked questions (FAQ)

🔹 How to enter formulas with crystalline hydrates (dots)?

The dot symbol (for example, in CuSO4·5H2O) is not yet supported. To calculate the mass, enter the two parts separately: first CuSO4, then 5H2O (or just H2O and multiply by 5), and add the results.

🔹 Why does chlorine have a fractional mass (35.45), and not a whole mass?

This is an IUPAC standard. Atomic mass is the average of all naturally occurring isotopes of an element. For precise laboratory work, rounding to the nearest whole number (35) is incorrect.

🔹 Are square brackets [] supported?

Yes, square brackets (common in complex joins) are treated the same as parentheses. You can safely enter formulas like [Cu(NH3)4]SO4.

🔹 Is there a limit on the length of the formula?

Technically, no. You can count masses of huge polymer chains. But if the formula is very long, the step-by-step description may take up a lot of space on the screen.

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