APA vs. MLA vs. Chicago: Which Citation Style Do You Need?

Quick answer: if your professor or journal didn't specify, check your field. APA is standard in psychology and the social sciences. MLA is standard in literature and the humanities. Chicago is standard in history. IEEE is standard in engineering and computer science. Vancouver is standard in medicine. Harvard is common in the UK, Australia, and business writing.

If you already know which style you need, jump straight to the generator: APA · MLA · Chicago · IEEE · Vancouver · Harvard

Which style is used in which field

APA vs. MLA: the two most commonly confused

These are the two styles students mix up most, because they're both used broadly across undergraduate coursework and look similar at a glance.

APA emphasizes the publication date — because in the social sciences, how recent a source is often matters as much as what it says. A citation looks like (Smith, 2024), and the reference list is alphabetical by author, with the year immediately after the name.

MLA emphasizes the author and page number — because in literary analysis, you're usually pointing to a specific passage, not just citing a finding. A citation looks like (Smith 42), no comma, no year in the parenthetical. The reference list ("Works Cited") is also alphabetical by author, but formatted differently from APA's "References" list.

The practical difference that trips people up: MLA doesn't put the year in the in-text citation at all — it's in the Works Cited entry, not the parenthetical. APA always includes it. If you're citing with a year inside the parentheses, you're doing APA, not MLA, whether or not that's what the assignment asked for.

Chicago: two different systems in one name

"Chicago style" actually refers to two distinct citation systems, and which one applies depends on the field:

• Notes-Bibliography: footnotes or endnotes, common in history and the humanities
• Author-Date: parenthetical citations similar to APA, common in the sciences

Check which one your assignment or publication actually wants — "use Chicago style" alone is ambiguous. The Chicago citation generator supports both.

IEEE and Vancouver: numbered citation systems

Both IEEE (engineering/CS) and Vancouver (medicine) use numbered, bracketed in-text citations — [1], [2] — tied to a numbered reference list in the order sources first appear, not alphabetically. If your field involves a lot of technical or clinical references packed into dense paragraphs, a numbered system keeps the text readable in a way author-date styles don't.

The two aren't interchangeable despite the shared numbering convention — formatting details in the reference list differ, so use the IEEE generator or Vancouver generator specifically, not one for the other.

Harvard: APA's close cousin

Harvard style is extremely close to APA — author-date parenthetical citations, alphabetical reference list — which is exactly why the two get confused. The differences are smaller formatting details (punctuation, "and" vs. "&", how page ranges are written) that vary further depending on which university's specific Harvard guide you're following, since "Harvard style" isn't governed by one central style manual the way APA and MLA are. Use the Harvard generator and double-check against your institution's specific guide if they publish one.

Still not sure which one you need?

Check your assignment brief or your target journal's author guidelines first — they'll usually state the required style explicitly. If they don't, the field table above is the next-best signal.

Once you've generated your citations in the right style, the next question is whether they're actually correct — real source, right author, right year, not something an AI tool quietly got wrong. Verify your bibliography free against six real academic databases, no card required.