Actual Yield Calculator

How to use the actual yield calculator

What this calculator does. This tool estimates actual yield, the quantity of product expected to be recovered after allowing for a reaction's percent yield. It multiplies the theoretical yield by the yield fraction. It is useful for checking laboratory planning, reviewing a stoichiometry exercise, comparing expected and recovered product, and preparing a concise calculation record. It does not balance a chemical equation, identify the limiting reactant, calculate molar mass, or verify that an experimental sample is pure.

When to use it. Use it before a laboratory run to estimate a realistic product mass, after a reaction to compare recovery with a theoretical target, while checking percent-yield homework, or when scaling a procedure while keeping the same assumed efficiency. The underlying relationship follows the standard definition described in the Chemistry LibreTexts explanation of theoretical, actual, and percentage yield.

How to calculate. The calculator opens with a complete demonstration: a theoretical yield of 19 g and a percent yield of 79%, producing an actual yield of 15.01 g. The example Excel workbook is available immediately.

1. Replace Theoretical yield with the maximum amount of product predicted from the balanced equation and limiting reactant.
2. Choose the matching Yield unit. The unit label changes without converting the numeric value because this selector declares the unit already used by the entered quantity.
3. Enter Percent yield as a percentage, such as 79 rather than 0.79.
4. Read Actual yield, Unrecovered amount, and Yield fraction, then review the calculation breakdown.
5. Select Download Excel to export the current inputs and outputs. Reset clears the demonstration values and disables export until a complete valid state is entered again.

Input guide. Theoretical yield is required, accepts a positive decimal number, and uses the selected yield unit. A realistic example is 19 g. Increasing it raises actual yield proportionally when percent yield stays fixed. Do not enter a unit symbol inside the field, use a decimal comma, or substitute the amount of reactant for the predicted amount of product. Yield unit is required and may be mg, g, kg, mol, mL, or L. The theoretical and actual yield must describe the same kind of quantity in the same unit; NIST's SI mass-unit guidance is useful when converting between milligrams, grams, and kilograms. Percent yield is required and accepts a nonnegative decimal percentage. A value of 79 means 79%, not 0.79%. Higher percentages increase actual yield. Values above 100 are accepted because they can flag wet, impure, contaminated, or incorrectly measured product, but they should be investigated rather than treated as ordinary reaction performance.

Output guide. Actual yield is the estimated recovered quantity in the chosen unit. It is driven by both inputs and is zero when percent yield is zero. Unrecovered amount is theoretical yield minus actual yield; it is positive below 100%, zero at 100%, and negative above 100%, which is a diagnostic sign rather than literal negative loss. Yield fraction is percent yield divided by 100 and is displayed as a decimal. The summary pills repeat the active unit and recovery percentage. The table lists each quantity, value, unit, and role using the same canonical model as the result cards and workbook.

Worked example. With a theoretical yield of 19 g and a percent yield of 79%, first convert 79% to the fraction 0.79. Then calculate 19 × 0.79 = 15.01 g. The unrecovered amount is 19 – 15.01 = 3.99 g. These values match the first-open result cards, table, and Excel checkpoints.