Used primarily as a labeled internal standard in analytical chemistry, especially in mass spectrometry and nuclear magnetic resonance (NMR) studies. Its deuterated methoxy group allows for precise tracking and quantification of benzoic acid derivatives in complex biological and environmental samples. This compound is valuable in metabolic studies, where it helps distinguish between endogenous and exogenous compounds due to its isotopic signature. It is also employed in pharmaceutical research to study drug metabolism and degradation pathways, providing accurate data in pharmacokinetic assays.