Chemistry toolkit
Chemistry calculators
Explore chemical quantities, solutions, equilibria, kinetics, gases, and thermochemistry using explicit formulas and units.
18 calculators
Choose a field of chemistry
Sections for electrochemistry and organic chemistry will appear when reviewed tools are published.
5 calculators
Chemical Quantities & Stoichiometry
Formula mass, the mole concept, particles, composition, and quantitative reaction relationships.
Empirical & molecular formula
Derive an empirical formula from elemental masses or percentages, then use measured molar mass to test the corresponding molecular formula.
Use calculator 01ChemistryOxidation numbers
Find one element’s oxidation number from a formula, total charge, and known states of the other elements, then verify the charge balance.
Use calculator 02ChemistryReaction stoichiometry
Find the limiting reagent, reactant leftovers, theoretical product yield, and optional percent yield from a balanced reaction.
Use calculator 03ChemistryMolar mass
Parse a chemical formula to calculate molar mass, atom counts, and each element’s mass percentage.
Use calculator 04ChemistryMoles, mass & particles
Convert among sample mass, amount in moles, and number of particles using molar mass and Avogadro’s constant.
Use calculator 054 calculators
Solutions & Concentration
Molarity, dilution, solution preparation, and concentration calculations.
ppm, ppb & molarity
Convert between molarity, mmol/L, mg/L, µg/L, ppm, ppb, and mass percent using explicit solute molar mass and solution density.
Use calculator 01ChemistryConcentration converter
Convert molarity, normality, mass percentage, and mass concentration using molar mass, solution density, and a defined equivalence factor.
Use calculator 02ChemistryMolarity & dilution
Calculate solution molarity or the final volume required for a dilution using transparent, classroom-ready formulas.
Use calculator 03ChemistrySolution mass percent
Calculate solute mass percentage from solute mass and total solution mass.
Use calculator 045 calculators
Acids, Bases & Equilibrium
pH, pOH, ion concentrations, buffers, titration, and chemical equilibrium.
Acid–base titration
Solve titration concentration and equivalence-volume problems with configurable stoichiometry, then estimate pH for strong acid–strong base titrations.
Use calculator 01ChemistrySolubility & Ksp
Convert between molar solubility and Ksp for a binary ionic solid, including stoichiometric ion powers and optional common-ion concentrations.
Use calculator 02ChemistryEquilibrium constants Kc & Kp
Build a concentration equilibrium expression, calculate Kc, or convert between Kc and Kp using temperature and the change in gaseous moles.
Use calculator 03ChemistrypH & pOH
Convert among pH, pOH, hydrogen-ion concentration, and hydroxide-ion concentration at 25 °C.
Use calculator 04ChemistryBuffer pH
Apply the Henderson–Hasselbalch equation to a weak-acid/conjugate-base buffer.
Use calculator 051 calculator
Reaction Kinetics
Rate laws, reaction orders, integrated kinetics, and concentration changes over time.
3 calculators
Gases & Thermochemistry
Gas-state relationships, energy transfer, enthalpy, and temperature-dependent chemistry.
Reaction enthalpy & Hess
Calculate reaction enthalpy from standard formation enthalpies or combine reversed and scaled thermochemical equations with Hess’s law.
Use calculator 01ChemistryIdeal gas law
Solve pressure, volume, amount, or absolute temperature with selectable units that are converted internally to SI.
Use calculator 02ChemistryCombined gas law
Calculate a final gas volume when pressure and absolute temperature change at constant amount of gas.
Use calculator 03