Systems and methods for pre-processing string data for network transmission are disclosed. A system can extract first sequences from a sequence file and generate respective encoded sequences based on the first sequences extracted from the sequence file. The system can generate a hash table that stores the respective encoded sequences. The system can combine at least two entries in the hash table based on a comparison of data generated from at least two of the respective plurality of encoded sequences. The system can transmit an output file including a plurality of decoded sequences generated based on the hash table.