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Reaction Stoichiometry Calculator

Reaction Stoichiometry Calculator
1. M
2. M
3. M
Calculate (unit):


Compute the stoichiometry of a chemical reaction and solve stoichiometry problems. The reaction stoichiometry calculator retrieves the final amount of the products (in moles, grams, or Mol) using the initial amounts of reactants (in moles, grams, liters, atmospheres, or bars), specifically of the limiting reactant, as the reactants in excess will not affect the amount of product.

* Calculations involving pressure assume ideal gas behavior.
* For scientific notation, use Ex to represent 10x (e.g. 1.7x105 would be input as 1.7E5).
* Check your input; inaccurate input value (e.g. non-existent element or unclosed parenthesis) may cause unexpected results. If the reaction is not balanced, a red border will appear around the product input box.
* Make sure to give values for all required inputs (e.g. if you are inputting a compound's partial pressure, you must also give the system's temperature and volume).
* For single compound stoichiometry, use the Single Compound Stoichiometry Calculator.
* For stoichiometry practice problems, visit the Practice Problems section.


  1. Enter up to three reactants and three products (separated by a +) in the Reactants and Products input boxes of the stoichiometry calculator.
  2. Select the appropriate units for the reactants and enter the amount of each reactant. If using units of volume, molarity must be given.
  3. Select the units that you would like the results to be in.
  4. If any of the reactants are given in units of pressure, enter the temperature and volume. Volume is also required if final amounts are to be given in units of molarity.
  5. Click Calculate to calculate the stoichiometric amounts of products.