Free Chemistry Calculators
Fast, accurate chemistry conversion calculators for moles, molar mass, molecular weight, molarity, molality, dilution, and stoichiometry — 100% free with step-by-step solutions.
Gram ↔ Mole Converter
Enter a mass or select from 150+ common substances. Get instant results with step-by-step solution.
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LiveAll 25 Chemistry Calculators
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⚗ 1. Mass & Mole Calculators
Convert mass in grams to moles using n = m/M with 150+ compound database.
Use Calculator →Calculate mass in grams from moles and molar mass (m = n × M).
Use Calculator →Solve for mass, moles, or molar mass in one unified tool.
Use Calculator →Type any chemical formula (e.g. H2SO4) to get molar mass & element breakdown.
Use Calculator →Calculate molecular mass and formula weight for compounds.
Use Calculator →Convert mass to total number of molecules via Avogadro's number.
Use Calculator →Convert grams directly to total number of atoms in a sample.
Use Calculator →Convert moles to particles using 6.022 × 10²³.
Use Calculator →Calculate total particles or moles using Avogadro's constant.
Use Calculator →📏 2. Molecular Weight Converters
Convert kilodaltons (kDa) to grams per mole (g/mol = kDa × 1,000).
Use Calculator →Convert molar mass in g/mol to protein kilodaltons (kDa).
Use Calculator →Convert atomic mass in Daltons (Da) to g/mol (1:1 equivalent).
Use Calculator →Convert molar mass in g/mol to Daltons (Da).
Use Calculator →Convert g/mol to kg/kmol (1:1 identical numerical ratio).
Use Calculator →Convert g/mol to mg/mmol (1:1 identical numerical ratio).
Use Calculator →💧 3. Concentration Calculators
Calculate molar concentration (mol/L) from moles/mass and volume.
Use Calculator →Convert mass concentration in g/L to molarity (mol/L).
Use Calculator →Convert g/mL mass density concentration to molarity.
Use Calculator →Calculate molality (mol/kg solvent) for colligative properties.
Use Calculator →Solve solution dilutions using C1V1 = C2V2 equation.
Use Calculator →⚗ 4. Stoichiometry & Chemistry Energy
Calculate mole ratios, reactant masses, and product yields.
Use Calculator →Determine empirical and molecular formulas from percent composition.
Use Calculator →Find elemental mass percentage breakdown from chemical formula.
Use Calculator →Identify the limiting reagent and excess reactant remaining.
Use Calculator →Convert specific energy (J/g) to molar energy (J/mol and kJ/mol).
Use Calculator →How Chemistry Calculations Work
Understanding the core concepts behind moles, molar mass, stoichiometry, and solution concentration.
Grams, Moles & Molar Mass
In chemistry, the mole is the bridge between the microscopic world of atoms and the macroscopic laboratory scale. One mole of any substance contains exactly 6.02214076 × 10²³ elementary entities (atoms, molecules, or formula units). The relationship between sample mass ($m$ in grams), number of moles ($n$ in mol), and molar mass ($M$ in g/mol) is governed by the core equation:
Molarity vs. Molality
Solution concentration can be measured in two main ways:
- Molarity (M or mol/L): Expresses moles of solute per liter of total solution ($C = n / V$). Molarity is volume-dependent and changes slightly with temperature.
- Molality (m or mol/kg): Expresses moles of solute per kilogram of solvent ($m = n / \text{kg}_{\text{solvent}}$). Because mass does not change with temperature, molality is essential for boiling point elevation and freezing point depression calculations.
Stoichiometry & Limiting Reactants
Stoichiometry uses balanced chemical equations to determine the quantitative relationships between reactants and products. The limiting reactant is the reactant that is completely consumed first, governing the theoretical yield of the reaction.
Popular Chemistry Calculations
Common conversion queries routed directly to our interactive calculators:
Enter chemical formula (e.g. H2O) in Grams to Moles Calculator →
50 kDa to g/mol50 kDa = 50,000 g/mol in kDa to g/mol Converter →
44 g/mol to kg/kmol44 g/mol = 44 kg/kmol in Molar Mass Converter →
Grams to MoleculesCalculate total molecules using Avogadro's constant →
Grams to AtomsConvert mass in grams to total number of atoms →
g/L to mol/LConvert mass concentration to molarity →
Frequently Asked Questions
Answers to the most common chemistry conversion questions.
How do I convert grams to moles?
Use the simple formula: moles (n) = mass (m) ÷ molar mass (M)
Example: Convert 36 grams of water (H₂O, molar mass = 18.015 g/mol):
n = 36 g ÷ 18.015 g/mol = 1.999 mol ≈ 2 mol
Use our calculator above to skip the manual math entirely!
What is a mole in chemistry?
A mole is the SI base unit for the amount of substance. One mole contains exactly 6.02214076 × 10²³ elementary entities (atoms, molecules, ions, etc.) — known as Avogadro's number.
Think of it like "a dozen" — except instead of 12 things, you have 602,214,076,000,000,000,000,000 things. Chemists use moles because atoms are too tiny to count individually.
How do I find the molar mass of a compound?
Add up the atomic masses of all atoms in the molecular formula, using the periodic table values:
Example for H₂O: (2 × 1.008) + (1 × 15.999) = 18.015 g/mol
You can also use our Molecular Weight Calculator to do this automatically — just type the formula!
What is the difference between molar mass and molecular weight?
Molar mass (g/mol) is the mass of one mole of a substance — a macroscopic property used in lab calculations.
Molecular weight (or relative molecular mass) is dimensionless — it's the ratio of the molecule's mass to 1/12 of a carbon-12 atom's mass.
Numerically they are equal (e.g., H₂O = 18.015 for both), but the units differ. In everyday chemistry, the terms are often used interchangeably.
Can I convert moles back to grams?
Yes! Use the reverse formula: mass (g) = moles (n) × molar mass (M)
Example: 2.5 mol of NaCl × 58.443 g/mol = 146.11 g
Switch to the "Moles → Grams" tab in our calculator above for instant conversion.
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