Percent Yield

Also known as actual over theoretical

%yield=mactualmtheoretical×100%\%\,\text{yield} = \frac{m_{\text{actual}}}{m_{\text{theoretical}}} \times 100\%

Enter your known values, leave one input blank, and solves for the missing one. Try different units for next level excitement!

Learning zone

A balanced equation promises a certain mass of product; the flask rarely delivers all of it. Side reactions consume reactant, some product stays dissolved in the mother liquor, and a little is always lost on filter paper and glassware. Percent yield is the honest scorecard: the mass you actually isolated divided by the stoichiometric maximum, times 100. In a classic teaching lab, synthesizing aspirin from salicylic acid might predict 5.00 g of product; if 4.21 g of dry crystals come off the funnel, the yield is 84.2%.

The number matters far beyond the classroom. Process chemists judge manufacturing routes largely by yield, because in a multi-step synthesis losses multiply — five steps at 80% each deliver only 33% overall. A reported yield above 100% is a red flag, not a triumph: it usually means the product is still wet or carries impurities.

Percent Yield
%yield=mactualmtheoretical×100%\%\,\text{yield} = \frac{m_{\text{actual}}}{m_{\text{theoretical}}} \times 100\%
Where
  • %yield\%\,\text{yield}= Percent yield
  • mactualm_{\text{actual}}= Actual yield (mass obtained)
  • mtheoreticalm_{\text{theoretical}}= Theoretical yield (mass predicted)
Missing one of these? Work it out first, then come back