In the framework of FAIRMODE activities concerning the harmonization of model validation methodologies, a specific task was dedicated to the development of a common standardized template to facilitate the screening and comparison of air quality forecast results. The proposed approach assesses the forecast model performances using, as a benchmark, the so called “persistence model”, which uses measurements of the previous day as an estimate for the full forecast prediction. Consistently with the FAIRMODE approach, the proposed formulation includes measurement uncertainty and relies on the definition of specific Model Quality Objective and Criteria. The main features of the methodology are described here, together with an example of its application to evaluate the quality of one year-long model data set produced by the Italian air quality forecast system FORAIR-IT. © British Crown Copyright (2022)