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Stoichiometry Calculator
Enter a reaction and the amount available for each reactant. See the balanced equation, limiting reactant and theoretical product yield.
How do I use this stoichiometry calculator?
Enter a neutral chemical reaction, then enter one amount for each reactant in the order shown. Choose grams or moles. The calculator balances the equation, compares each amount with its coefficient, and estimates every product. Optionally enter the actual mass of one product to calculate percent yield.
Frequently asked questions
How do I use this stoichiometry calculator?
Enter a neutral chemical reaction, then enter one amount for each reactant in the order shown. Choose grams or moles. The calculator balances the equation, compares each amount with its coefficient, and estimates every product. Optionally enter the actual mass of one product to calculate percent yield.
Are my reaction or measurements uploaded?
No. The reaction and amounts are calculated in this browser and are not uploaded or saved.
How is the limiting reactant found?
The calculator converts each reactant amount to moles, then divides by that reactant’s balanced-equation coefficient. The smallest ratio limits the reaction. If the ratios tie within rounding tolerance, all tied reactants are shown.
How is theoretical yield calculated?
The limiting reactant determines the maximum reaction extent. The balanced coefficient ratio gives the theoretical moles of each product, and the supported molar mass converts those moles to grams.
Can percent yield be greater than 100%?
Yes, the calculator reports the value from the masses entered. A result above 100% can point to moisture, impurities or measurement errors; it does not prove a reaction was more than complete.
Which reactions and elements are supported?
This educational tool accepts supported neutral molecular formulas and the element set documented by the UsefulVerse molar-mass calculator. Ionic charges, half-reactions and electron balancing are not supported.