Theoretical Yield Calculator

This calculator works out the theoretical yield of a chemical reaction, the maximum mass of product that could form, based on the limiting reagent. In any reaction, one reactant runs out first, the limiting reagent, and it sets the ceiling on how much product can be made; no matter how much of the other reactants you have, you cannot exceed what the limiting reagent allows. The theoretical yield is that maximum, assuming the reaction goes perfectly to completion with no losses. It is the benchmark against which the actual, real-world yield is compared to judge how efficient a reaction was, and calculating it is a core skill in quantitative chemistry. This calculator does it through the standard mole route. You enter the mass of the limiting reagent, its molar mass, the mole ratio of product to reagent from the balanced equation, and the molar mass of the product, and the calculator returns the theoretical yield in grams, along with the moles of limiting reagent and of product. The results update as you type. Use it for chemistry study, for planning a synthesis, or as the basis for a percent yield calculation. The method converts the mass of the limiting reagent to moles by dividing by its molar mass, applies the mole ratio to find the moles of product, then converts those moles to a mass by multiplying by the product's molar mass. The mole ratio comes straight from the coefficients of the balanced equation, for example two to one if two moles of product form per mole of reagent, so balancing the equation correctly is essential. The theoretical yield assumes everything reacts and nothing is lost, which never quite happens in practice, so the actual yield is always lower; dividing the actual yield by this theoretical yield gives the percent yield, the standard measure of reaction efficiency. Identifying the limiting reagent first is the key step, since it alone determines the maximum product.

Theoretical yield = (reagent mass / reagent molar mass) x mole ratio x product molar mass. The mole ratio comes from the balanced equation. Assumes complete reaction with no losses.