Abstract-In general, books are not appropriate for all ages, so the aim of this work was to find an effective method of representing the age suitability of textual documents, making use of automatic analysis and visualization. Interviews with experts identified possible aspects of a text (such as 'is it hard to read?') and a set of features were devised (such as linguistic complexity, story complexity, genre) which combine to characterize these age related aspects. In order to measure these properties, we map a set of text features onto each one. An evaluation of the measures, using Amazon Mechanical Turk, showed promising results. Finally, the set features are visualized in our age-suitability tool, which gives the user the possibility to explore the results, supporting transparency and traceability as well as the opportunity to deal with the limitations of automatic methods and computability issues.Index Terms-Information interfaces and presentation, information search and retrieval.