The fast-paced diffusion of Open Government Data (OGD) in the last few years in Italy has highlighted the need for a high standard of data quality to ensure that this data can be used to effectively support decision-making, transparency, and innovation. This thesis aims to carry out a massive analysis of Italian open data quality by measuring its accuracy, availability, completeness, consistency, and understandability as defined by the ISO/IEC 25012 and ISO/IEC 25024 standards. To this end, a tool has been developed and applied on a large and diverse collection of data and metadata. A pipeline of automated processes is used to perform data discovery, data normalization, and data quality assessment, the output of which is then stored into a PostreSQL database.