The document describes solGS, a web-based tool for genomic selection in plant and animal breeding. solGS allows users to store genotype and phenotype data, compose training populations, build prediction models using RR-BLUP or GBLUP, predict breeding values for selection candidates, and perform additional analyses like estimating genetic correlations and calculating selection indices. The tool addresses challenges of large genomic data volumes and enables data cleaning, imputation, statistical modeling, and interactive visualization. Models are fitted using 10-fold cross-validation, and solGS provides options for composing training populations by trait, trial, or custom individual lists.