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.