๐งชLimiting Reagent Calculator
Enter a balanced chemical equation and the amount of each reactant to find the limiting reagent, theoretical yield, and leftover excess.
Free Limiting Reagent Calculator
Not sure which reactant runs out first? Our free Limiting Reagent Calculator finds the answer instantly. Enter a balanced chemical equation and the amount of each reactant you have โ in grams or moles โ and it converts everything to moles, compares against the stoichiometric ratios, and identifies exactly which reactant limits the reaction.
From there it calculates the theoretical yield of your chosen product and tells you how much of each excess reactant is left over once the reaction is complete. Every step of the mole-ratio comparison and yield calculation is shown, so you can follow the reasoning rather than just seeing a final number.
Built for stoichiometry homework and lab prep, it runs entirely in your browser โ no sign-up, no downloads, and no limits on how many reactions you check. See the About page or the FAQ for more.