About the Limiting Reagent Calculator
Find the limiting reactant, theoretical yield, and leftover excess for any balanced reaction.
What it is
In any chemical reaction with more than one reactant, one reactant typically runs out first โ the limiting reagent โ which determines how much product can form. This tool parses a balanced chemical equation, converts your entered reactant amounts to moles, compares them against the stoichiometric ratios, and identifies the limiting reagent, theoretical yield, and excess reactant remaining.
Features
Equation parsing
Enter any balanced equation with any number of reactants and products.
Grams or moles per reactant
Each reactant has its own unit toggle, with molar mass computed automatically.
Mole-ratio comparison table
See every reactant's moles-divided-by-coefficient value side by side.
Theoretical yield & excess
Full working for the product yield and how much of each other reactant is left over.