An online platform for the management of digital visual data for the condition monitoring of protective coatings on marine steel structures The paper presents an online platform for the annotation and management of visual digital data, which allows for the condition monitoring and maintenance modelling of protective coatings of marine steel structures by means of digital image data only. A 10‐step procedure is introduced which includes the data acquisition, transfer of the data into the online platform, the annotation and management of the data by means of special tools and methods, and the modelling for condition monitoring and maintenance purposes. Some special applications of the platform are exemplary illustrated. [ABSTRACT FROM AUTHOR]