Ecosystem models are always simplifications of reality and as such their application for ecosystem-basedmanagement requires standard validation. Here, the "DataReli" toolbox is proposed to evaluate the qualityof the data used during the construction of ecosystem models, their coherence across trophic levels, andwhether data limitations prevent the model long-term applications. This toolbox is the combinationof three operational and complementary analyses: (i) the pedigree index to determine to what extenta model was calibrated on data of local origin; (ii) the graphical analysis known as PREBAL to assesswhether a model respects some basic ecological and fisheries principles; and (iii) a sensitivity analysis toevaluate the robustness of model predictions to small variations in input data. The toolbox is delivered topotential users with main generic recommendations on how interpreting results conjointly and on whichdecisions to make about parameters’ revisions or model uses' restrictions. (i) Corrections of parametersshould be preferentially envisaged when modelling data-rich environments. (ii) For those models withan overall pedigree index above 0.4, a closer look at the pedigree routine, i.e. values by parametersand compartments, and the PREBAL analysis would help to prioritize parameters needing improvement.(ii)' For Ecopath models of no overall acceptable quality (overall pedigree index