In addition to Male or Female, Facebook now lets US users choose among some 50 additional options such as "transgender," "cisgender," "gender fluid," "intersex" and "neither."
Users also now have the ability to choose the pronoun they would like to be referred to publicly: he/his, she/her, or the gender-neutral they/their.
"When you come to Facebook to connect with the people, causes, and organizations you care about, we want you to feel comfortable being your true, authentic self," Facebook said in a post on its Diversity page.
"An important part of this is the expression of gender, especially when it extends beyond the definitions of just 'male' or 'female,' " the post continued. "So today, we're proud to offer a new custom gender option to help you better express your own identity on Facebook."