Morphologically classifying embryos is important for numerous laboratory techniques, which range from basic methods to methods for assisted reproduction. However, the standard method currently used for classification is subjective and depends on an embryologist’s prior training. Thus, our work was aimed at developing software to classify morphological quality for blastocysts based on digital images. Methods The developed methodology is suitable for the assistance of the embryologist on the task of analyzing blastocysts. The software uses artificial neural network techniques as a machine learning technique. These networks analyze both visual variables extracted from an image and biological features for an embryo. Results After the training process the final accuracy of the system using this method was 95%. To aid the end-users in operating this system, we developed a graphical user interface that can be used to produce a quality assessment based on a previously trained artificial neural network. Conclusions This process has a high potential for applicability because it can be adapted to additional species with greater economic appeal (human beings and cattle). Based on an objective assessment (without personal bias from the embryologist) and with high reproducibility between samples or different clinics and laboratories, this method will facilitate such classification in the future as an alternative practice for assessing embryo morphologies.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Estadual Paulista Júlio de Mesquita Filho, Assis, Av. Dom Antônio, Parque Universitário, CEP 19806900, SP, BrasilUniversidade Estadual Paulista Júlio de Mesquita Filho, Assis, Av. Dom Antônio, Parque Universitário, CEP 19806900, SP, BrasilLaboratory of Applied Mathematics (Laboratório de Matemática Aplicada - MaAp), School of Sciences and Letters (Faculdade de Ciências e Letras – FCL) São Paulo State University (Universidade Estadual Paulista – Unesp), Assis, BrazilLaboratory of Embryo Micromanipulation (Laboratório de Micromanipulação Embrionária - LaMEm), FCL/Unesp, Assis, BrazilCiencias BiologicasFAPESP: 2011/06179-7FAPESP: 2006/06491-2