Percent Yield Calculator

What is Percent Yield?

Percent yield is a measure of the efficiency of a chemical reaction. It compares the actual amount of product obtained to the theoretical maximum amount that could be produced based on stoichiometry.

How to Use This Calculator

1. Enter the theoretical yield - this is the maximum amount of product that could be formed based on the limiting reactant and balanced chemical equation.
2. Enter the actual yield - this is the amount of product that was actually obtained from the reaction.
3. Click the Calculate button to compute the percent yield.
4. The result will be displayed as a percentage.

Example Calculation

Suppose you are performing a reaction that theoretically produces 50 grams of product (theoretical yield). After conducting the experiment, you measure that you obtained 45 grams of product (actual yield).

Using the calculator:
Percent Yield = (45 g / 50 g) × 100% = 90%

This means your reaction was 90% efficient.

Interpreting Results

• A percent yield of 100% indicates perfect efficiency
• A percent yield less than 100% indicates some product was lost during the reaction (e.g., due to side reactions, incomplete reactions, or purification losses)
• A percent yield greater than 100% is physically impossible in normal chemical reactions and may indicate measurement errors or the presence of impurities