By providing diverse news content, news media are key for a well-functioning public sphere. However, agreement on how to measure news content diversity is lacking. Research often refers to democratic theory as normative reference point, but diﬀerent models of democracy understand news content diversity diﬀerently. Our study makes a unique, innovative contribution to this ﬁeld: (1) We develop a methodological framework for measuring news content diversity, that is a set of comprehensive measuring instruments that derive diﬀerent operationalizations of topic and actor diversity each from liberal and deliberative democratic theories. (2) Considering that a good public discourse requires more than diversity, we analyze news content diversity in the context of four other journalistic standards: neutrality, rationality, discursivity, and civility. (3) We prove the applicability of our measuring instruments by means of a standardized content analysis of six German news media as a case study. The diﬀerent quality proﬁles of these outlets our analysis reveals are explained by their diﬀerent functions in the media system. Our study shows how important a multi-perspectival normative approach to news content diversity is, both empirically and theoretically. Future studies on news content diversity should make their normative foundations transparent and derive their indicators purposefully therefrom.