One of the major challenges in the emerging field of microbiomics is the bias and errors introduced in the complex workflows. Besides nucleic acid purification, bias also arises from sequencing library preparation and subsequent processes. The ZymoBIOMICS Microbial Community DNA Standard is designed to assess bias, errors and other artifacts after the step of nucleic acid purification. This DNA standard is created by pooling DNA extracted from pure cultures. It has an accurately defined composition, negligible impurities (0.01%), and contains genomes of a wide range of GC content (15% - 85%). This DNA standard is designed to have the same microbial composition with the cellular version, the ZymoBIOMICS Microbial Community Standard, so that they can be more powerful when working in tandem. Theoretical Composition Based on Genomic DNA: Listeria monocytogenes - 12%, Pseudomonas aeruginosa - 12%, Bacillus subtilis - 12%, Escherichia coli - 12%, Salmonella enterica - 12%, Lactobacillus fermentum - 12%, Enterococcus faecalis - 12%, Staphylococcus aureus - 12%, Saccharomyces cerevisiae - 2%, and Cryptococcus neoformans - 2%.