Enter the formula
Type the chemical formula using correct element symbols, numbers, and grouping marks.
Chemistry calculator
Molar Mass Calculator
Enter any valid chemical formula to calculate its molar mass, atom count, elemental mass, and percentage composition in a clear breakdown.
Parentheses support
Hydrate formulas
Percentage composition
Formula input
Enter a compound
Use standard chemical symbols and numbers. Element capitalization is important.
Quick examples
Supported formula syntax
You can use elements, numbers, parentheses, square brackets, coefficients, and hydrate dots. Examples include Fe2(SO4)3, K4[Fe(CN)6], and CuSO4·5H2O.
Calculated result
Composition breakdown
Your result will appear here
Enter a valid chemical formula to view molar mass and element percentages.
Simple calculation process
How the molar mass calculator works
The calculator analyzes your formula structure, counts every atom, applies atomic weights, and presents a complete result.
Analyze its structure
Parentheses, brackets, coefficients, and hydrate sections are expanded automatically.
Apply atomic masses
Each atom count is multiplied by the standard atomic weight of its element.
Review the result
View the total molar mass, atom counts, subtotals, and percentage composition.
What is a molar mass calculator?
A molar mass calculator is a chemistry tool that calculates the mass of one mole of a compound from its chemical formula. The answer is normally given in grams per mole, or g/mol.
Every chemical element has an atomic mass. A chemical formula tells you which elements are present and how many atoms of each element are included. The calculator multiplies each atomic mass by its atom count and adds the values together.
The molar mass formula
The general calculation can be written as:
Molar mass = Σ (number of atoms × atomic mass)
Why molar mass is important
Molar mass connects the microscopic number of particles in a substance with a measurable mass in grams. It is regularly used in stoichiometry, laboratory preparation, chemical equations, and concentration calculations.
Supported chemical formulas
- Simple formulas such as H2O, CO2, NaCl, and NH3
- Molecular formulas such as C6H12O6
- Parentheses such as Ca(OH)2
- Nested groups such as K4[Fe(CN)6]
- Hydrate formulas such as CuSO4·5H2O
- Leading coefficients such as 2H2O
Helpful answers
Frequently asked questions
Learn more about formulas, atomic weights, hydrates, and molar mass calculations.
What is molar mass?
Molar mass is the mass of one mole of a substance. It is normally expressed in grams per mole, written as g/mol.
How is molar mass calculated?
Molar mass is calculated by multiplying the atomic mass of each element by the number of atoms present and then adding all element totals together.
Can I calculate formulas with parentheses?
Yes. The calculator supports formulas containing parentheses and square brackets, including Ca(OH)2, Al2(SO4)3, and K4[Fe(CN)6].
Does this calculator support hydrate formulas?
Yes. You can calculate hydrate formulas such as CuSO4·5H2O. A regular period can also be used instead of the middle dot.
What does percentage composition mean?
Percentage composition shows the percentage of the total compound mass contributed by each individual element.
Are the results accurate?
The calculator uses commonly accepted standard atomic weights. Results are suitable for normal educational and chemistry calculations.
Can I enter chemical subscripts?
Yes. You may enter regular numbers such as H2O or Unicode subscript numbers such as H₂O.