Most fields mandate one citation style. Picking the wrong one is a fast way to get a desk reject, so it's worth knowing the differences. You can format any of these automatically with our free citation generator.
IEEE - engineering and computer science
IEEE uses numbered in-text citations in square brackets, like [1], in the order sources first appear. The reference list is numbered to match. Author names are given as initials then surname. Expect IEEE for most engineering, CS, and electronics venues.
APA - social sciences
APA uses author-date in-text citations, like (Smith, 2020). The reference list is alphabetical by author surname, with the year in parentheses near the front. APA emphasizes the date because recency matters in the social sciences. Expect APA in psychology, education, and nursing.
MLA - humanities
MLA uses author-page in-text citations, like (Smith 42), with no comma and no year. The reference list is titled "Works Cited" and is alphabetical by author. Expect MLA in literature, languages, and cultural studies.
Chicago - history and some humanities
Chicago has two systems: notes-bibliography (footnotes plus a bibliography, common in history) and author-date (similar to APA, common in the sciences). Which one you use depends on the discipline and the publisher's instructions.
Quick comparison
- IEEE:
[1]- numbered, by order of appearance. - APA:
(Smith, 2020)- author and year. - MLA:
(Smith 42)- author and page. - Chicago: footnote¹ or
(Smith 2020)depending on the system.
Always defer to the specific journal or instructor's guidelines - many venues have house variations on these base styles.