The relations between self-reported aspects of gender identity and sexuality were studied in an online sample of cisgender (n = 4,954), transgender (n = 406), and gender-diverse (n = 744) groups. Aspects of gender identity and sexual fantasies, attraction, behavior, and romantic relations were assessed using the Multi-gender Identity Questionnaire (Multi-GIQ) and a sexuality questionnaire. Results show a wide spectrum of gender experiences and sexual attractions within each group, an overlap among the groups, and very weak relations between atypical gender identity and atypical sexuality. At the group level, aspects of gender identity and sexuality were mainly predicted by gender and sex-gender configuration, with little contribution of sex assigned at birth. A principal component analysis (PCA) revealed that measures of gender identity and of sexuality were independent, the structure of sexuality was mostly related to gender, whereas the structure of gender identity was mostly related to sex-gender configuration. The results of both approaches suggest that measures of gender identity could roughly be divided into three classes: one including feeling as a man and feeling as a woman; a second including measures of nonbinary and “trans” feelings; and a third including feeling as a “real” woman and feeling as a “real” man. Our study adds to current scientific data that challenge dichotomous conventions within gender identity and sexuality research. Possible social and clinical implications are discussed.