The National Deuteration Facility (NDF) at ANSTO is co-funded by the National Collaborative Research Infrastructure Strategy (NCRIS), an Australian government initiative, for the provision of deuterated molecules to researchers through an open access scheme. These molecules are used to investigate complex chemical and biological systems using a variety of different characterization techniques including NMR spectroscopy. Their applications are quite diverse, which include studies of metabolic pathways, elucidation of mechanisms of chemical or enzymatic reactions, micro-analytical tracing, and as internal standards in pharmaceuticals for quantitative analyses and bioanalytical investigations. In the synthesis of these deuterated compounds or in the investigations that use them, it is necessary to use a reliable technique to quantify the deuterium content at each molecular site without the need of isolating and purifying the target compound. Site specific deuterium level quantification becomes challenging when dealing with non-specifically or randomly deuterated compounds that are produced by metal catalyzed hydrothermal reactions in D2O, one of the most convenient and popular deuteration methods. In this presentation, we will report an NMR method to quantify the level of isotopic labelling in deuterated molecules using the deuterium isotope effect on quaternary 13C NMR chemical shifts [1]. We have performed several approaches to quantify the deuterium content at different specific sites to demonstrate a convenient and generic analysis method for use in randomly deuterated molecules. The reported method provides fast accumulative 13C NMR spectral acquisition to quantify deuterium that can be used for a range of applications.