Molar Mass Calculator

Use this free browser-based tool to calculate the molar mass of any chemical compound instantly. Simply enter a chemical formula (like H2O, CO2, NaCl), and get accurate results in seconds. No data is uploaded — everything is calculated directly in your browser.

Chemical Formula

Result

About Molar Mass Calculator

The Molar Mass Calculator helps you quickly determine the molar mass of chemical compounds. Just enter a valid chemical formula, and the tool will compute the total mass based on atomic weights.

What Does It Do?

How To Use It

  1. Enter a chemical formula (e.g., H2O)
  2. Click “Calculate Molar Mass”
  3. View results instantly

Popular Use Cases

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All Chemistry Tools

Mm
Calculate the molar mass of a compound from its formula.
EF
Derive the simplest whole-number ratio formula from % composition data.
Convert between moles and grams using molar mass.
%
Calculate percent yield from actual and theoretical yield.
LR
Identify which reactant will be exhausted first and yield maximum product.
Calculate new concentration or volume using C1V1 = C2V2.
ST
Compute moles or mass of reactants/products in a chemical reaction.
Balance chemical equations by adjusting coefficients.
pH
Compute pH given the hydrogen ion concentration.
Convert between pH and pOH values in aqueous solutions.
M→N
Convert molarity to normality based on equivalent factors.
N→M
Convert normality to molarity using equivalents.
Compute pressure, volume, moles or temperature from PV=nRT.
q=mcΔT
Calculate heat energy given mass, specific heat, and temperature change.
½-life
Calculate remaining quantity after a given half-life period.
M
Compute molarity from moles of solute and volume of solution.
N
Calculate solution normality based on equivalents and volume.
E°
Determine the standard cell potential for a redox reaction.
Calculate rate constant from half-life for first-order kinetics.
c
Calculate specific heat needed for temperature change.
Compute change in boiling point due to solute addition (ΔTb = Kb·m).
Calculate ΔTf = Kf·m for solutions with solutes.
π
Calculate osmotic pressure using π = iMRT.
pH = pKa
Find pH of buffer solutions using pH = pKa + log(A⁻/HA).
Ksp
Compute solubility product constant and ion concentrations.
s
Find molar solubility from known Ksp values.
Ka
Convert between pKa and Ka values (pKa = −log Ka).
Kb
Convert between pKb and Kb values.
ΔG
Compute ΔG = ΔH − TΔS for reactions at constant T.
Calculate heat change for reactions (ΔH).
ΔS
Find the entropy change of a reaction or process.
Compute rate constant using k = Ae^(−Ea/RT).
k₂/k₁
Find k₂/k₁ using Arrhenius relationship at two temperatures.
ρ
Calculate gas density using ρ = PM/RT.
P₁
Compute partial pressure of a gas in a mixture using mole fraction.
χ
Find mole fraction of a component in a mixture.
m
Calculate molality from moles of solute and solvent mass.
i
Compute number of particles dissociated per formula unit.
%
Find percent composition of each element in a compound.
6.022×10²³
Convert between moles and number of particles using 6.022×10²³.
MF
Find the molecular formula from molar mass and empirical data.
iso
Compute average atomic mass based on isotopic abundances.
%
Calculate the purity percentage of a given chemical sample.
%
Find the percent composition for each element in a compound.
#
Count total atoms of each element in a given formula.
Identify oxidation and reduction processes in a reaction.
Ox
Determine oxidation states of elements in compounds or ions.
n
Calculate number of moles using PV = nRT or molar volume.
Compute the gas volume at STP or given conditions from moles.
PT
View element data, atomic numbers, and periodic trends.