Credibility of online news media is facing important challenges: the levelling effect of the digital environment, the changing habits of consumption, polarization of discourses... This scenario makes it relevant to address what features of news brands and news content shape the credibility of contemporary journalism. This article tests a set of items, including journalistic standards, reputation and citizen participation, in order to build predictors involved in credibility judgments. The authors carried on a quantitative survey (n=416), representative of the Spanish online population. Results identified currency of information, inclusion of analysis and context, citation of sources and inclusion of links to primary sources as the most significant predictors of credibility judgements; it also showed that engaged respondents rely on news brand reputation and individual journalists´ reputation and do not take into account ideological affinity with editorial lines of media. Participation in the media did not prove to be relevant in shaping aggregated judgments of credibility.