The Stoichiometry Calculator instantly computes limiting reactants, excess amounts, theoretical yields, and percent yields using balanced chemical equations and input quantities in grams, moles, or volumes.
Stoichiometry is the branch of chemistry that quantifies relationships between reactants and products in reactions, relying on mole ratios from balanced equations to predict outcomes like limiting reagents and yields. It enables precise calculations for experiments, ensuring efficient use of materials.
Our completely free Stoichiometry Calculator requires no registration, no limits, and no payments. Enter the balanced equation, reactant amounts (with auto-conversions for grams to moles, molarity to moles, or STP volumes), and select options for purity adjustments or multi-step reactions—it delivers accurate results, step-by-step breakdowns, and verified examples in seconds. The tool excels on mobile and desktop with a clean, ad-free interface that prioritizes privacy and speed.
Suited for chemistry students, educators, and lab professionals, it addresses semantic concepts such as mole conversions, empirical formulas, reaction stoichiometry vs composition, and common pitfalls while providing trustworthy outputs (e.g., in 2H₂ + O₂ → 2H₂O with 4 mol H₂ and 1 mol O₂, O₂ limits at 2 mol H₂O theoretical). Achieve reliable reaction planning with unparalleled ease.