Techniques and solutions are described for storing and processing metadata models using a metadata hub that can be accessed by a plurality of computing systems. The metadata hub can receive requests to retrieve or store metadata models. The metadata models can be converted between first and second formats. In some cases, the second format can be a relational format, such as a representation of a metadata model as one or more records in one or more database tables. The metadata hub can be used to compare metadata models, including comparing a metadata model provided by a client system with one or more metadata models stored in a repository maintained by the metadata hub. In at least some cases, the metadata model provided by the client system is not stored. The repository can be queried to find related metadata models, or to find metadata models meeting specified search criteria.