A citation is only useful if someone can follow it back to the exact passage you read. PDFs make that harder than most sources: there's no page on the web to link to, the metadata is often incomplete, and three different style guides — APA, MLA, and Chicago — treat the same document differently. This guide gives you accurate rules for all three, shows you where to find the details you need inside the file, and covers what to do when the obvious fields are missing.
What you need before you start
Before you open your style guide, gather the source details. The same five fields appear in every style:
- Author(s). The person or organisation named on the cover page or title page. For a journal article inside a PDF, the article's author is what you need, not the journal.
- Title. The full title of the document, and for a journal article, the article title and the journal title separately.
- Date. The year of publication — look at the cover page, the copyright notice, or the footer. For an updated report, use the revision date.
- Publisher or source. For a report or book: the organisation or press that published it. For a journal article: the journal name, volume, issue, and page range.
- URL or DOI. A DOI (Digital Object Identifier) is preferred over a URL when available, because DOIs are stable. URLs for PDFs break frequently.
If any of these are missing, don't panic — Step 5 below covers the fallbacks.
Step 1 — Find the PDF's source details
Locate the author, title, publication date, publisher or journal, URL or DOI, and page count — usually on the cover page, title page, or header. For a journal article, note the volume, issue, and page range too.
For a government or institutional report, the "author" is often the organisation (e.g. "World Health Organization" or "U.S. Bureau of Labor Statistics"). Treat the organisation as the author for in-text citations too.
For a journal article in PDF form, the article and the journal are two different things. The article title goes where the book title would go; the journal name goes where the publisher would go, alongside the volume, issue, and page span.
Step 2 — Choose your citation style
Confirm which style your institution or publication requires — APA, MLA, or Chicago — since each formats the same details differently. When in doubt, check your style guide or ask your instructor.
The three most common styles each have a different philosophy:
- APA (American Psychological Association) — prioritises the author and date. Used heavily in social sciences, psychology, and education.
- MLA (Modern Language Association) — prioritises the author and page. Used in humanities and literature.
- Chicago — two variants: Notes-Bibliography (common in history and the arts) and Author-Date (used in sciences). For PDFs, the Notes-Bibliography style is more often encountered.
If you are writing for a journal, check the journal's own author guidelines — they sometimes specify a variant of a style that differs from the default.
Step 3 — Write the in-text citation
Insert a brief reference in the body of your writing at the point where you quote or paraphrase: APA uses (Author, Year, p. X), MLA uses (Author page), and Chicago footnotes the full source on first use.
APA in-text:
(World Health Organization, 2022, p. 14)
MLA in-text:
(World Health Organization 14)
Chicago footnote (first use):
World Health Organization, Global Health Observatory Data (Geneva: WHO, 2022), 14.
For a direct quotation, always include the page number if one is visible. For a paraphrase, APA and Chicago encourage a page number; MLA requires it for direct quotes but not for paraphrases.
Step 4 — Build the reference-list entry
Construct the full citation in your Works Cited, References, or Bibliography using your style's author–date–title–source pattern, then add a DOI or direct URL if the PDF is available online.
APA (7th edition) — standalone PDF report
World Health Organization. (2022). Global health observatory data repository. https://www.who.int/data/gho
Structure: Author, A. A. (Year). Title of work: Subtitle if any. Publisher. URL or DOI
APA — journal article in PDF form
Karimi, L., & Meyer, D. (2021). Emotional labour and burnout. Journal of Occupational Health, 63(1), e12212. https://doi.org/10.1002/1348-9585.12212
MLA (9th edition) — standalone PDF report
World Health Organization. Global Health Observatory Data Repository. WHO, 2022, www.who.int/data/gho.
Structure: Author. Title. Publisher, Year, URL.
MLA — journal article in PDF form
Karimi, Leila, and David Meyer. "Emotional Labour and Burnout." Journal of Occupational Health, vol. 63, no. 1, 2021, https://doi.org/10.1002/1348-9585.12212.
Chicago (Notes-Bibliography, 17th edition) — standalone PDF report
World Health Organization. Global Health Observatory Data Repository. Geneva: WHO, 2022. https://www.who.int/data/gho.
Chicago — journal article in PDF form
Karimi, Leila, and David Meyer. "Emotional Labour and Burnout." Journal of Occupational Health 63, no. 1 (2021). https://doi.org/10.1002/1348-9585.12212.
A citation in a reference list is only as useful as its ability to lead the reader back to the source. Use a DOI over a URL wherever one exists — DOIs are resolved by publishers and do not break when a site restructures.
Step 5 — Handle a missing author, date, or page
Substitute the document title for a missing author, mark a missing date per style ("n.d." in APA and Chicago; omit it in MLA), and use a section heading (or "n.p." in MLA and Chicago) when there are no page numbers — each style has a documented fallback, so the citation stays complete and verifiable.
No author:
- APA: Move the document title to the author position. In-text: (Global health observatory, 2022, p. 14).
- MLA: Move the title to the author position in Works Cited. In-text: (Global Health 14).
- Chicago: List the title first in the bibliography entry.
No date:
- APA: Use "n.d." for "no date" — (World Health Organization, n.d., p. 14).
- MLA: Omit the date entirely — MLA 9th does not use "n.d." as a fallback.
- Chicago: Write "n.d." in the year position of the footnote or bibliography entry.
No page numbers:
- APA: Paragraph number (para. 3), section heading, or timestamp for multimedia. Example: (World Health Organization, 2022, Introduction section, para. 2).
- MLA: Use the section heading as the locator, or omit it if none applies.
- Chicago: Section heading or "n.p." for no page.
A scanned PDF is a special case: if OCR has not been run on it, there may be no selectable text and no reliable page numbers at all. In that case, cite the document as you would any print source and note that the version you consulted was a scanned file.
Verifying a citation after you write it
A citation's job is to let someone else — or you in six months — find the exact passage you used. Once you have written it, test it: can you click the DOI or URL and land on the document? Can you navigate to the page or section you cited? A scroll-to-source citation in a PDF reading tool makes this check automatic, but doing it by hand is still worthwhile for the final reference list.
If you are citing a PDF that lives in a research tool or reading app, the Sidenote citations page explains how Sidenote attaches a verifiable citation to every claim it makes about a document — so the pointer from claim to source is always there.
Common questions about citing PDFs
Do I need to say it is a PDF in my citation?
Generally no. APA 7th edition removed the '[PDF]' label that earlier editions recommended. MLA and Chicago do not require it either. Cite the source — report, article, book — as you would the print version, and add the URL or DOI so the reader can access your specific copy.
What if the PDF has no DOI and the URL keeps changing?
Cite the URL you accessed and add an access date in MLA and Chicago (APA does not require one unless the content changes frequently). If the URL is very long or unstable, link to the publisher's landing page or the database record for the document instead of the direct PDF link.
How do I cite a PDF that is just a scanned image with no text?
Treat it as you would any non-digitised print source: cite the original document's author, title, date, and publisher, and add the location where you accessed it — a library database, an archive URL, or a physical call number. Note in your citation that it is a scanned copy if the format is relevant.
Can I cite a PDF the same way regardless of what type of document it is?
No — the PDF format does not determine the citation format. Cite a PDF of a journal article as a journal article, a PDF of a book chapter as a book chapter, and a PDF of a government report as a report. The container (PDF) is secondary to the source type.
What is the difference between a DOI and a URL for citation purposes?
A DOI (Digital Object Identifier) is a persistent identifier assigned by the publisher that resolves to the source regardless of where it is hosted. A URL is an address that can change. For academic and professional work, always prefer a DOI when one exists — it is far less likely to produce a dead link in a year's time.