The article provides basic knowledge on how to calculate selectivity of ‘genetic zipper’ (‘GZ’) tech-nology-based oligonucleotide pesticides to provide safety for non-target organisms. Also here we rep-resent 500 oligonucleotide pesticides computationally predicted and generated in one day via the DNAInsector web tool (dnainsector.com). 11 nucleotides long pesticides targeting pests’ pre-rRNA and rRNA provide high species specificity and theoretical selectivity at the level of 1 in 4,194,304. None of the 500 computationally predicted oligonucleotide pesticides coincide with each other and this essentially shows that for any ecosystem, even if it consists of closely related species, it is possible to create selectively acting oligonucleotide pesticides. ‘GZ’ technology is a smart approach transfer-ring us to new possibilities of development of potent and selective oligonucleotide pesticides based on new principles prompted by nature.