Atom-to-atom mapping (AAM) is a procedure that establishes a one-to-one correspon-dence between the atoms in the reactants and products of a chemical reaction. AAM provides the information of the chemical structure transformation, including the identification of bonds broken and formed, as well as reaction centers. This information is crucial for various applications, such as retrosynthesis planning, reaction classification, 5 chemical reaction searching, as well as clarifying mechanisms of enzymatic reactions or discovering metabolic pathways. Consequently, AAM plays a significant role in developing chemical reaction databases, which are used extensively in chemoinformatics research. AAM has been accomplished through manual curation by expert chemists or automatic algorithms. However, manual AAM is a laborintensive and time-consuming process that relies on expert chemical knowledge, so it becomes impractical as the complexity and scale of chemical datasets increase. Thus, automated approaches have become prominent.