Free Chemistry Calculators

Molar Mass Calculator | Molecular Weight

Calculate the molar mass of common chemical elements and simple compounds.

Molarity Calculator | M = n/V

Calculate molarity, moles, or volume of solutions using M = n/V formula.

pH Calculator | pH, pOH & Ions

Calculate pH, pOH, [H⁺], and [OH⁻] concentrations for acids and bases.

Dilution Calculator | C₁V₁=C₂V₂

Solve any variable in C₁V₁ = C₂V₂ and generate serial dilution tables. Supports M, mM, µM, mg/mL, ppm and more.

Stoichiometry Calculator | Moles & Grams

Convert between moles and grams using molar mass. Calculate mass from moles and vice versa.

Periodic Table | Interactive Element Reference

Explore the full periodic table with detailed element data including atomic number, mass, electron configuration, electronegativity, density, melting point, and category. Search by name, symbol, or atomic number.

Percent Yield Calculator | Actual vs Theoretical Yield

Calculate percent yield, theoretical yield, or actual yield for any chemical reaction. Enter grams or moles, and get step-by-step stoichiometry working showing mole conversions, limiting reagent identification, and yield analysis.

Limiting Reagent Calculator | Find Limiting Reactant

Find the limiting reagent, excess reactant, and theoretical yield for any balanced chemical reaction. Enter masses or moles of two reactants, and get complete stoichiometric working with mole ratios and yield calculations.

Empirical Formula Calculator | From Mass or Percent

Find the empirical formula and molecular formula from mass percentages or grams of each element. Enter up to 6 elements, and see step-by-step mole calculations, ratio simplification, and molecular formula determination from molar mass.

Significant Figures Calculator | Count, Round & Arithmetic

Count significant figures in any number, round to N sig figs, and perform addition, subtraction, multiplication, and division with automatic sig fig rules applied. Supports scientific notation and explains which rule was used.

Henderson-Hasselbalch Calculator | Buffer pH

Calculate buffer pH using the Henderson-Hasselbalch equation: pH = pKa + log([A⁻]/[HA]). Solve for pH, pKa, or the acid/base ratio. Includes buffer capacity, weak base support, and common buffer presets for acetate, phosphate, TRIS, HEPES, and bicarbonate.

Chemical Equilibrium Calculator | ICE Table, Kc, Kp & Le Chatelier

Solve chemical equilibrium problems using ICE tables. Enter stoichiometry, equilibrium constant Kc or Kp, and initial concentrations to find equilibrium concentrations. Computes the reaction quotient Q, determines the direction of shift, and predicts Le Chatelier responses to perturbations.

Nernst Equation Calculator | Cell Potential at Non-Standard Conditions

Calculate electrochemical cell potential at any temperature and concentration using the Nernst equation E = E° − (RT/nF)ln Q. Supports concentration cell calculations (E° = 0), temperature variation, and solving for unknown ion concentrations when the measured potential is known.

Beer-Lambert Law Calculator | Absorbance, Transmittance & Concentration

Apply the Beer-Lambert law A = εlc to compute absorbance, percent transmittance, molar absorptivity (ε), path length, or concentration from any four known quantities. Supports multi-wavelength analysis and mixture concentration estimation.

Colligative Properties Calculator | Boiling Point Elevation & Freezing Point Depression

Compute the four colligative properties of solutions: boiling point elevation (ΔTb), freezing point depression (ΔTf), osmotic pressure (π), and vapor pressure lowering (ΔP). Supports electrolyte solutions via the van't Hoff i-factor for common solvents.

Arrhenius Equation Calculator | Activation Energy, Rate Constant & Half-Life

Compute the Arrhenius rate constant k, activation energy Ea, pre-exponential factor A, and reaction half-life using k = Ae^(−Ea/RT). Given two rate constants at two temperatures, back-calculates Ea. Shows temperature effect on rate with a comparison table.