Math & Science
Stoichiometry Calculator
Calculate quantities in chemical reactions
Formulas and edge cases are reviewed against authoritative references before publication. For methodology, editorial standards, or corrections, use the links below.
Frequently asked questions
How do I enter equations?
Use + for reactants/products, -> for yields: H2 + O2 -> H2O
What is limiting reactant?
The substance that runs out first, determining maximum product yield.
How is theoretical yield calculated?
From stoichiometry assuming 100% conversion of limiting reactant.
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About this tool
This Stoichiometry Calculator turns your inputs into practical results. Provide Known Amount, Required/Produced Amounts, and Chemical Equation to calculate Balanced Equation and Required/Produced Amounts.
Adjust values to compare scenarios and see how sensitive the result is. The calculation uses the numbers as entered, so double-check units and expect small differences from rounding in the displayed totals.