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Chemistry Calculators71 calculators

Chemistry can be complex, but the right calculator can turn a challenge into a quick solution. This collection is designed for real-world use in classrooms and labs, from balancing equations to checking pH or finding molar mass. Students find help with homework and lab reports, while researchers save time on common calculations. Each calculator tackles a specific problem faced in chemistry classes or experiments, letting you focus on the science itself instead of manual math. Take a look through the tools here and see how much simpler chemistry can be when the calculations are handled for you.

Acids/Bases

5 calculators

Atomic Structure

5 calculators

Electrochemistry

4 calculators

Gases

9 calculators

Kinetics & Reactions

5 calculators

Nuclear

2 calculators

Solutions

14 calculators

Bleach Dilution Calculator

Calculate how much bleach to add to water for a desired sodium hypochlorite concentration. Supports household and industrial bleach strengths.

Concentration Converter Calculator

Convert between concentration units: molarity, mass percent, ppm, ppb, and mg/L. Uses molecular weight and solution density for accurate conversions.

Dilution Calculator

Calculate dilution using the C1V1 = C2V2 equation. Solve for any of the four variables.

Dilution Factor Calculator

Calculate the dilution factor for simple and serial dilutions. Find final concentration from initial concentration and dilution steps.

Dilution Ratio Calculator

Calculate dilutions for cleaning solutions and chemicals. Convert between ratios (1:X) and concentrations. Find concentrate and diluent volumes.

Ion Concentration Calculator

Calculate individual ion concentrations and ionic strength from dissolved salts in solution.

Mass Percent Calculator

Calculate mass percent (weight percent) of a solute in a solution: mass% = (mass of solute / mass of solution) × 100.

Molality Calculator

Calculate molality (m), moles of solute, or mass of solvent using the formula m = moles / kg solvent.

Molarity Calculator

Calculate molarity (M), moles, or volume using the formula M = moles / liters. Solve for any variable.

Mole Fraction Calculator

Calculate mole fractions of components in a mixture. Supports 2 or 3 component mixtures with verification that fractions sum to 1.

Serial Dilution Calculator

Calculate concentrations at each step of a serial dilution. Find final concentration, total dilution factor, and volumes needed.

Solution Preparation Calculator

Calculate how much solute to weigh and solvent to add to prepare a solution of desired molarity and volume.

Water Hardness Calculator

Convert water hardness between ppm, gpg, mmol/L, dGH, and Clark degrees. Classify water as soft, moderately hard, hard, or very hard.

Water Potential Calculator

Calculate water potential using the equation Ψ = Ψs + Ψp. Find solute potential with the van't Hoff equation Ψs = -iCRT.

Stoichiometry

16 calculators

Avogadro's Number Calculator

Convert between moles, particles, and grams using Avogadro's number (6.022 × 10²³).

Combustion Analysis Calculator

Determine the empirical formula of an organic compound from combustion analysis data (CO₂ and H₂O produced).

Empirical Formula Calculator

Determine the empirical formula of a compound from percent composition or mass data of its elements.

IUPAC Nomenclature Calculator

Apply IUPAC nomenclature rules to a simple open-chain organic compound. Returns the systematic name, parent chain stem, numbered locants, and the root-plus-suffix breakdown.

Limiting Reagent Calculator

Determine the limiting reagent, excess reagent, and theoretical yield from moles or grams of two reactants.

Molar Mass Calculator

Calculate the molar mass of a compound from element counts. Enter the number of atoms for each element and get the total mass in g/mol.

Molar Volume Calculator

Calculate molar volume of a gas at STP or any temperature and pressure using the ideal gas law.

Mole Calculator

Convert between moles, grams, and number of particles. Calculate any value given the other two.

Molecular Formula Calculator

Determine the molecular formula from an empirical formula and experimental molar mass.

Molecular Weight Calculator

Calculate the molecular weight (molar mass) of common compounds or custom molecules by entering element counts.

Percent Composition Calculator

Calculate the percent composition by mass of each element in a compound using atomic masses and the molecular formula.

Percent Purity Calculator

Calculate the percent purity of a substance from direct mass measurements or from titration data.

Percent Yield Calculator

Calculate percent yield from actual yield and theoretical yield. Assess how efficient your reaction was.

Reaction Yield Calculator

Calculate percent yield, actual yield, or theoretical yield: % yield = (actual / theoretical) × 100.

Stoichiometry Calculator

Calculate reactant or product quantities using mole ratios from balanced chemical equations.

Theoretical Yield Calculator

Calculate the theoretical yield of a chemical reaction from reactant mass, molar masses, and the mole ratio.

Thermochemistry

11 calculators

Beer-Lambert Law Calculator

Calculate absorbance, concentration, molar absorptivity, or path length using the Beer-Lambert law: A = εbc. Also computes transmittance.

Boiling Point Elevation Calculator

Calculate the boiling point elevation of a solution using ΔTb = i × Kb × m. Supports water, ethanol, benzene, and custom solvents.

Bond Energy Calculator

Estimate reaction enthalpy from bond energies. ΔH = Σ(bonds broken) - Σ(bonds formed). Enter bond types and counts for reactants and products.

Calorimetry Calculator

Calculate heat absorbed or released using q = mcΔT. Supports common substances with preset specific heat values.

Colligative Properties Calculator

Calculate boiling point elevation, freezing point depression, and vapor pressure lowering for solutions.

Enthalpy Calculator

Calculate the heat of reaction (q = mcΔT), enthalpy change, or calorimetry results for chemical reactions.

Entropy Change Calculator

Calculate entropy change (ΔS) for phase changes, temperature changes, and ideal mixing. Assess spontaneity using the second law of thermodynamics.

Freezing Point Depression Calculator

Calculate the freezing point depression of a solution using ΔTf = i × Kf × m. Supports water, benzene, cyclohexane, and custom solvents.

Gibbs Free Energy Calculator

Calculate Gibbs free energy using ΔG = ΔH - TΔS to determine reaction spontaneity.

Hess's Law Calculator

Calculate reaction enthalpy from formation enthalpies using Hess's Law: ΔH_rxn = Σ(ΔHf products) - Σ(ΔHf reactants).

Photon Energy Calculator

Calculate the energy of a photon from its wavelength or frequency using E = hf = hc/λ.