APA, MLA and Chicago ask for nearly the same facts about a source: who wrote it, what it is called, where it appeared, and when. What changes is the order of those facts, the punctuation between them, and what shows in your own sentences when you point to the source.
Each choice suits the writing the style was made for. An author-date citation keeps the age of every finding in front of the reader. An author-page citation sends the reader to the exact passage. Chicago offers both.
This page puts the three side by side, cites one journal article in each, and ends with the rule that settles which one to use. It is published by EdCitation, whose Cite a source sets that same article in APA, MLA and Chicago author-date from the publisher's record.
What is the difference between APA, MLA and Chicago?
The main difference is what the citation in your text contains: APA gives the author and the year, MLA gives the author and the page number, and Chicago gives either a footnote number or the author and the year. Here are the three citation styles compared on the points that decide how a paper looks.
| APA | MLA | Chicago | |
|---|---|---|---|
| Current edition | 7th (2020) | 9th (2021) | 18th (2024) |
| Most used in | Psychology, education, nursing, business, the social sciences | Literature, languages and other humanities | History, literature and the arts (notes and bibliography); sciences and social sciences (author-date) |
| Citation in the text | (Dittmar & Schemske, 2023) | (Dittmar and Schemske 480) | A footnote number, or (Dittmar and Schemske 2023, 480) |
| Page number in the text | Required for quotations, written as p. 480 | Given when you cite a specific passage, with no "p." | Given when you cite a specific passage, with no "p." |
| Name of the list | References | Works Cited | Bibliography (notes system) or reference list (author-date) |
| Where the date goes | Straight after the authors, in brackets | Near the end of the entry | After the authors in author-date, near the end in a bibliography |
| Authors' first names | Initials only | In full | In full |
| Titles of articles and books in the list | Sentence case | Title case | Title case |
| Place of publication for a book | Never given | Never given | No longer required, from the 18th edition |
| Page range punctuation | En dash, no spaces | Hyphen in student work | En dash |
| Built in EdCitation | APA 7 | MLA 9 | Author-date only |
The two rows that cost the most marks
The first is capitalisation. APA lowers most words in an article or book title in the reference list, even when the journal printed them with capitals, while MLA and Chicago capitalise the main words. The American Psychological Association (2026) puts the rule plainly in its own reference guide: capitalise only the first letter of the opening word, of any word after a colon, and of proper nouns, and leave the article title in roman type. The name of the journal keeps its capitals and its italics in all three styles.
The second is the name of the list. A paper in APA style headed "Works Cited" tells the marker that the style guide was not opened. The names are set out in Reference list, bibliography or works cited.
What does the same source look like in APA, MLA and Chicago?
The same article carries the same facts in every style, arranged differently. Here is one article from The American Naturalist, by Emily L. Dittmar and Douglas W. Schemske, cited four ways. It is the article the Chicago Manual of Style uses in its own author-date sample, so the Chicago entry below can be checked against the publisher's page.
APA 7
Dittmar, E. L., & Schemske, D. W. (2023). Temporal variation in selection influences microgeographic local adaptation. The American Naturalist, 202(4), 471–485. https://doi.org/10.1086/725865
In the text: (Dittmar & Schemske, 2023), or for a quotation (Dittmar & Schemske, 2023, p. 480).
MLA 9
Dittmar, Emily L., and Douglas W. Schemske. "Temporal Variation in Selection Influences Microgeographic Local Adaptation." The American Naturalist, vol. 202, no. 4, Oct. 2023, pp. 471-85, https://doi.org/10.1086/725865.
In the text: (Dittmar and Schemske 480).
Chicago 18, author-date
Dittmar, Emily L., and Douglas W. Schemske. 2023. "Temporal Variation in Selection Influences Microgeographic Local Adaptation." American Naturalist 202 (4): 471–85. https://doi.org/10.1086/725865.
In the text: (Dittmar and Schemske 2023, 480).
Chicago 18, notes and bibliography
- Emily L. Dittmar and Douglas W. Schemske, "Temporal Variation in Selection Influences Microgeographic Local Adaptation," American Naturalist 202, no. 4 (2023): 480, https://doi.org/10.1086/725865.
Dittmar, Emily L., and Douglas W. Schemske. "Temporal Variation in Selection Influences Microgeographic Local Adaptation." American Naturalist 202, no. 4 (2023): 471–85. https://doi.org/10.1086/725865.
What moved, and why
APA reduces first names to initials, joins two authors with an ampersand, puts the year second, writes the article title in sentence case, and italicises the volume number but not the issue number or the brackets around it. MLA labels the volume and the issue ("vol." and "no."), adds "pp." before the pages, and places the date late. Chicago author-date starts like MLA and places the year like APA.
Two small things surprise people. The first is the journal's name: Chicago's own sample reads American Naturalist, without "The". The 18th edition now keeps an initial The in running text when it is part of a periodical's official name, while allowing it to be dropped in the citation itself, so both forms are defensible in a Chicago paper as long as you are consistent. The second is the punctuation of the page range. APA's own examples use an en dash with no spaces and give both numbers in full. The Modern Language Association (n.d.-b) says hyphens are used in the MLA Handbook and in student examples because they are easier for students to type, while publishers use en dashes.
All three now write a DOI as a full link beginning with https://doi.org/. APA leaves no full stop after it. MLA and Chicago end the entry with one. There is more on this in What is a DOI.
How many authors does each style list?
The three styles cut a long author list at different points, and the point where they cut is one of the most common sources of error in a reference list.
| Number of authors | APA 7 in the text | APA 7 in the list | MLA 9 in the text | MLA 9 in the list | Chicago 18 in the note or citation | Chicago 18 in the list |
|---|---|---|---|---|---|---|
| One | Dittmar (2023) | Named | Dittmar (480) | Named | Dittmar | Named |
| Two | Dittmar and Schemske (2023) | Both named | Dittmar and Schemske (480) | Both named | Dittmar and Schemske | Both named |
| Three | Grady et al. (2023) | All three named | Grady et al. (210) | First, then et al. | Grady et al. | All three named |
| Six | Grady et al. (2023) | All six named | Grady et al. (210) | First, then et al. | Grady et al. | All six named |
| Seven or more | Grady et al. (2023) | Up to 20 named | Grady et al. (210) | First, then et al. | Grady et al. | First three, then et al. |
Two details are easy to miss. The University of Chicago Press (n.d.-d) sets the bibliography limit at six names, with the first three and "et al." beyond that, and cuts the note or in-text citation to the first author and "et al." from three authors on. That is stricter in notes than the 17th edition was, so a guide written for Chicago 17 will tell you something different.
MLA is stricter still about what you write in your own sentences. The Modern Language Association (n.d.-c) reserves "et al." for the works-cited list and for parenthetical citations: when you name a multi-author work in prose, you either write the names out or give the first author "and others". "Grady and others argue" is MLA; "Grady et al. argue" is not.
For APA, the Publication Manual (7th edition) lists up to 20 authors in a reference and, at 21 or more, gives the first 19, an ellipsis and the final author. That rule comes from the manual: APA's own website was behind a security check on the day of writing, so we could not re-read its page for it. There is more on the in-text side in When to use et al..
Which citation style should I use?
Use the style named in your assignment brief, your module handbook or your department's guide, because that instruction beats every general rule about subjects. APA says as much itself: its student paper setup guide tells students that instructors' guidelines take precedence over APA Style (American Psychological Association, n.d.). If the brief runs to several pages, EdCitation's Check your paper reads it into a checklist, the named style included, so the answer is not lost in the small print.
If nothing is written down, work through these in order:
- Ask. A one-line message to your teacher or tutor settles it, and shows care.
- Look at the reading list. The journals and textbooks of your subject show its habit. Open two or three and see how they cite.
- Follow the subject. If you still have no answer, the "Most used in" row of the table is a fair guide.
- Then stay with it. One style, applied the same way from the first citation to the last entry, reads better than a mixture of two.
If the brief only says "Chicago"
There is a second choice to make, and it changes the whole paper. The University of Chicago Press (n.d.-b) publishes two systems: notes and bibliography, favoured in literature, history and the arts, and author-date, favoured in the sciences and social sciences. Footnotes and a "Bibliography" heading are one paper; brackets in the text and a "References" heading are another. If your brief says only "Chicago", ask which is meant before you write, because converting a finished paper from one to the other means rewriting every citation. EdCitation builds the author-date system only, so in a notes-and-bibliography paper the footnotes and bibliography are set by hand from the patterns above.
In secondary school the choice is usually between MLA and APA, and the teacher's instructions say which. There is a guide for a first paper in How to cite sources in your first research paper.
What about Harvard, IEEE and Vancouver?
Harvard, IEEE and Vancouver are the three other styles a student is most likely to be given, and each belongs to a region or a field.
- Harvard is an author-date style, close to APA in the text: (Dittmar and Schemske, 2023). It has no single rulebook. Many UK universities follow the version in Cite Them Right, and others publish their own, which is why two universities can mark the same reference differently. See the Harvard referencing guide.
- IEEE is a numbered style used in engineering and computing. A number in square brackets, such as [1], stands in the text, and the list at the end runs in the order in which sources were first cited, not in alphabetical order.
- Vancouver is the numbered style of medicine and the health sciences. Sources are numbered in the order in which they are first mentioned, and the detailed formats come from the US National Library of Medicine's guide, Citing Medicine.
The practical difference is what happens when you add a source late. In an author-date style you drop the new entry into its alphabetical place and nothing else moves. In a numbered style, inserting a source at paragraph three renumbers everything after it.
How do I get a reference right in any of these styles?
The reliable way is to start from the publisher's record of the source and let the style rules arrange it, not to retype the details by hand. Many formatting errors begin as typing errors: a missing issue number, a title copied in capitals, a DOI with a character dropped.
EdCitation's Cite a source is the best tool for this, because it looks the work up rather than writing the reference, which a chatbot composing references from patterns cannot do. From a DOI, a title, a PubMed ID or an ISBN it finds the record, sets the reference in APA 7, MLA 9 or Chicago 18 author-date, or in Cite Them Right Harvard, IEEE or Vancouver, and screens the source for retraction. The record carries details a retyped reference loses: the MLA entry above dates the Dittmar and Schemske article by its issue, Oct. 2023, and EdCitation dates a journal article in MLA the same way.
One thing still needs your eye when you switch styles. The table above shows APA wants sentence case where MLA and Chicago want title case. Cite a source sets an APA title in sentence case and keeps names and initialisms, so glance at any name made of ordinary words; its MLA and Chicago entries keep the capitals the publisher deposited, so a title stored in sentence case is raised by hand for them.
Building a reference is free, with no account, and Verify references, also free, checks the finished list against the records. A free account keeps a reference list in the dashboard, each reference taggable and set in its own style: a list you can copy with its italics or download as Word, BibTeX or RIS. Pro, at $8 a month, brings References from a file for a whole paper, and the Max plan, at $24 a month, Theoretics QA and the Library (pricing). A tool arranges the facts. It cannot know what your brief says, so check the brief first.
Quick questions
Is APA or MLA easier?
Neither is harder than the other. MLA in-text citations are shorter, because they carry no year, while APA entries follow one fixed pattern of author, date, title and source. The easier style is the one your course uses all year.
Can I use APA if my teacher asked for MLA?
No. Use the style that was asked for, because the work is marked against it. APA's own guidance says an instructor's instructions come before APA Style, and the same holds the other way round.
What are the current editions of APA, MLA and Chicago?
The current editions are the 7th edition of the APA Publication Manual, which APA itself cites with the year 2020, the 9th edition of the MLA Handbook (2021) and the 18th edition of The Chicago Manual of Style (2024). Guides written for older editions give different rules, so check which edition a guide follows before you copy its pattern.
What changed in Chicago's 18th edition?
The changes that reach a student paper are the loss of the required place of publication in book citations, tighter limits on how many authors are named in notes and bibliographies, and new guidance on citing AI-generated material. A paper built from a Chicago 17 guide will still be readable, but it will not match.
Is Chicago the same as Turabian?
Turabian is a version of Chicago style written for students, from the same publisher. Its citation forms follow Chicago's, with extra guidance on how to format a student paper. If your brief says Turabian, the Chicago patterns on this page apply.
Can one tool give me a reference in APA, MLA and Chicago?
Yes. EdCitation's free Cite a source sets one source in APA 7, MLA 9 or Chicago 18 author-date from the publisher's record; its APA titles come in sentence case, and in MLA and Chicago check the title's capitals, which follow that record.
References
- American Psychological Association. (n.d.). Student paper setup guide. APA Style. https://apastyle.apa.org/instructional-aids/student-paper-setup-guide.pdf
- American Psychological Association. (2025). APA Style common reference examples guide. APA Style. https://apastyle.apa.org/instructional-aids/reference-examples.pdf
- American Psychological Association. (2026). Reference guide for journal articles, books, and edited book chapters. APA Style. https://apastyle.apa.org/instructional-aids/reference-guide.pdf
- International Committee of Medical Journal Editors. (n.d.). Recommendations: Preparing a manuscript for submission to a medical journal. ICMJE. https://www.icmje.org/recommendations/browse/manuscript-preparation/preparing-for-submission.html
- Modern Language Association. (n.d.-a). In-text citations: An overview. MLA Style Center. https://style.mla.org/in-text-citations-overview/
- Modern Language Association. (n.d.-b). Should a hyphen or an en dash be used for inclusive page ranges? MLA Style Center. https://style.mla.org/hyphen-or-dash-page-ranges/
- Modern Language Association. (n.d.-c). When a work by three or more authors is mentioned in the text of a research paper, should the names of all the authors be included? MLA Style Center. https://style.mla.org/when-a-work-by-three-or-more-authors-is-mentioned-in-the-text-of-a-research-paper-rather-than-in-a-parenthetical-citation-should-the-names-of-all-the-authors-be-included-or-only-the-first-one-foll/
- University of Chicago Press. (n.d.-a). Author-date: Sample citations. The Chicago Manual of Style Online. https://www.chicagomanualofstyle.org/tools_citationguide/citation-guide-2.html
- University of Chicago Press. (n.d.-b). Chicago-style citation quick guide. The Chicago Manual of Style Online. https://www.chicagomanualofstyle.org/tools_citationguide.html
- University of Chicago Press. (n.d.-c). Notes and bibliography: Sample citations. The Chicago Manual of Style Online. https://www.chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html
- University of Chicago Press. (n.d.-d). What's new in the 18th edition. The Chicago Manual of Style Online. https://www.chicagomanualofstyle.org/help-tools/what-s-new.html