Percent Yield Calculator
Find reaction yield from actual and theoretical amounts.
How much did the reaction give?
Percent yield measures the efficiency of a chemical reaction: how much product you actually got compared with the theoretical maximum. Real reactions always fall short of the ideal.
Getting 8.2 grams from a reaction that should give 10 is an 82% yield. Chemists use it to gauge how well a synthesis worked and where product was lost.
Practical and private
The calculation runs in your browser, so nothing you enter is uploaded.
Frequently Asked Questions
What is percent yield?
The actual amount of product obtained as a percentage of the theoretical maximum from the reaction.
Why is it below 100%?
Side reactions, losses, and incomplete reactions mean real yields rarely reach the theoretical amount.
What units?
Any, as long as actual and theoretical use the same unit — grams, moles, or litres.
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