Percent Yield Calculator
Find percent yield from the actual amount of product you got and the theoretical amount you expected.
Result
Percent Yield85%
Actual yield: 8.5 g
Theoretical yield: 10 g
Calculation working
How it was calculated
Percent Yield = Actual Yield ÷ Theoretical Yield × 100
8.5 g ÷ 10 g × 100
= 85%
What is percent yield?
Percent yield tells you how much product you actually obtained compared with the amount the reaction was expected to produce.
Percent yield formula
% Yield = (Actual Yield ÷ Theoretical Yield) × 100
- Actual yield —
- the amount of product you actually obtained.
- Theoretical yield —
- the maximum amount expected from the reaction based on stoichiometry.
How it works
Three short steps
Find the actual yield
Weigh or measure the product you actually obtained.
Find the theoretical yield
Calculate the maximum amount the reaction should produce.
Divide and multiply by 100
Actual ÷ theoretical × 100 gives the percent yield.
Worked example
8.5 ÷ 10 × 100
= 85%
Need more?
Need to find the theoretical yield?
Theoretical yield normally comes from stoichiometry and the limiting reactant. These tools calculate it:
FAQ
Frequently asked questions
What is percent yield?
Percent yield compares what you actually obtained with what the reaction was expected to produce: (actual ÷ theoretical) × 100.
How do I calculate percent yield?
Divide the actual yield by the theoretical yield and multiply by 100. For 8.5 g actual and 10 g theoretical: (8.5 ÷ 10) × 100 = 85%.
Can percent yield be over 100%?
It can happen, and it usually points to moisture, impurities, measurement error, or an incorrect theoretical yield. This calculator shows the value with that note instead of rejecting it.
What is the difference between actual and theoretical yield?
Actual yield is the amount of product you actually obtained. Theoretical yield is the maximum amount expected from the reaction based on stoichiometry.
What if my actual and theoretical yields have different units?
Matching mass units (g with mg, for example) convert automatically, as do mol with mol. If one value is in grams and the other is in moles, enter the product's molar mass so the calculator can compare them.
How do I find theoretical yield from a chemical equation?
Balance the equation, find which reactant runs out first, and convert its amount into product.