How to Cite ChatGPT in APA, MLA, and Chicago (2026 Rules)

When You Actually Need a Citation

You cite ChatGPT when its output appears in your final work. That includes direct quotes from the response, paraphrased ideas that came from the model, generated images or charts, translated text, and data it produced.

You do not need a citation when AI only helped you brainstorm, outline, or check grammar, and none of its specific wording or ideas survived into the final draft. You may still need to disclose the use in a methods note, but that is different from a formal citation.

When in doubt, disclose. A short footnote saying "I used ChatGPT to brainstorm topic ideas" is much safer than a missing acknowledgment.

APA Style (7th Edition, 2026 Update)

APA treats the company that built the model (OpenAI, Anthropic, Google) as the author. The model name is treated like the title. You include the version, the year, the date of the conversation, and a stable URL where possible.

Reference list entry.

OpenAI. (2026). ChatGPT (May 14 version) [Large language model]. https://chat.openai.com/

In-text citation. (OpenAI, 2026)

Including the prompt. APA recommends preserving the exact prompt and the response in an appendix when the conversation matters. In the body, you can describe the prompt and quote the response:

When prompted with "Explain the difference between Type I and Type II errors," ChatGPT responded that "a Type I error is rejecting a true null hypothesis…" (OpenAI, 2026).

Use the same pattern for Claude (author: Anthropic) and Gemini (author: Google).

MLA Style (9th Edition, 2026 Update)

MLA is the outlier. It explicitly says not to treat AI tools as authors, because AI does not meet MLA's definition of authorship. Instead, the prompt becomes the title-like element and the AI tool is listed as the container.

Works Cited entry.

"Explain the difference between Type I and Type II errors." prompt. ChatGPT, 14 May version, OpenAI, 14 May 2026, chat.openai.com.

In-text citation. ("Explain the difference")

Note: MLA also requires you to disclose AI use in a note or in your methodology, even if the AI did not produce text that appears verbatim in your paper.

Chicago Style (17th and 18th Editions)

Chicago is flexible. The 17th edition added guidance to treat AI similarly to personal communications: cite in a footnote, not in the bibliography, unless your instructor wants otherwise. The 18th edition (released late 2025) added more detail and now allows full bibliography entries.

Footnote (17th and 18th).

1. ChatGPT, response to "Explain the difference between Type I and Type II errors," OpenAI, May 14, 2026, https://chat.openai.com/.

Bibliography entry (18th only).

OpenAI. ChatGPT. Large language model. Accessed May 14, 2026. https://chat.openai.com/.

Chicago's flexibility means "check your professor's preference" is the actual rule.

Citing Other AI Tools (Claude, Gemini, Copilot, Perplexity)

The patterns extend cleanly.

• Claude. Author: Anthropic. Title: Claude (Opus 4.7 version) or whichever model you used.
• Gemini. Author: Google. Title: Gemini (3 Pro version).
• Microsoft Copilot. Author: Microsoft. Title: Copilot.
• Perplexity. Author: Perplexity AI. Title: Perplexity.
• GitHub Copilot for code. Cite the model used (often GPT-4-class), follow Chicago footnote pattern, include a disclosure note in your methodology.

What to Include in an AI Disclosure Statement

Even when a citation is not strictly required, most universities now expect a disclosure note. A complete one answers five questions.

1. Which tool did you use, and which version?
2. What did you use it for? (Brainstorming, outlining, drafting, editing, translation, code, image generation, data analysis.)
3. Where in the document did its output appear, even if rewritten?
4. How did you verify the output? (Cross-checked against sources, ran the code, etc.)
5. Did your instructor or institution permit this use?

Common Citation Mistakes

1. Treating ChatGPT as if it had a human author named "ChatGPT." In APA, the author is OpenAI.
2. Using MLA but listing OpenAI as the author (MLA explicitly says not to).
3. Forgetting to include the version or date of the conversation.
4. Citing the AI but not disclosing what you used it for.
5. Citing AI when you only used it for spell-check (you usually do not need to).
6. Not citing AI when you should have, especially when paraphrased ideas survived into the final draft.

If Your School Has Its Own Rule

The published style guide rules above are the defaults. A growing number of universities now have stricter institutional policies that override these defaults: some require a separate AI declaration form, some require highlighted passages, some prohibit AI use entirely on certain assignment types.

Check your syllabus and your school's academic integrity page before you cite. The wrong rule applied confidently looks worse than asking.

If you want to skip the format-juggling, our free citation generator handles APA, MLA, and Chicago for traditional sources. For AI tools, paste your generated citation into the relevant field, double-check the format against the examples above, and put a disclosure note in your methodology.