1-Isopropyl-4-nitrobenzene-d4 is the deuterium-labeled analogue of 1-isopropyl-4-nitrobenzene supplied for research and analytical applications. It is formulated as a stable isotope reference material intended for use as an internal standard, tracer, or reference in mass spectrometry, NMR, and mechanistic studies, with high isotopic labeling and analytical purity.