The required number of reads depends on factors such as genome size, the number of known genes, and transcripts. As a general guideline, we recommend 5-10 million read pairs per sample for small genomes (e.g., bacteria), and 20-30 million reads per sample for larger genomes (e.g., human, mouse). For medium-sized genomes (e.g., yeast), the required number of reads can vary based on the project, but we typically suggest between 15-20 million reads per sample. For de novo transcriptome assembly projects, we recommend around 100 million reads per sample.