Does your assignment ask for parentheses or footnotes?
Chicago has two citation systems. Author-date uses citations in parentheses with a reference list. Notes and bibliography uses raised numbers that point to footnotes or endnotes. This page starts in Author-Date; check your assignment before choosing.
Chicago author-date format
A basic parenthetical citation gives the author’s last name and year, followed by a comma and a page number when needed. There is no comma between the name and the year, but n.d. takes one: (Name, n.d.). Enter the page you used in the Page field; it changes the citation for the current source.
Use one surname for one author and both surnames for two authors. For three or more authors, use the first surname followed by et al. Enter all the authors in the tool so the reference list can use the right number of names.
If a work has no author, use its title in place of the name; a long title can be shortened in the text citation. For an undated web page, use n.d. in place of the year. Include an access date in the reference entry, or identify a dated archived version. Confirm that an author or date is truly absent before checking the corresponding box.
For works by the same author in the same year, add a, b and so on to the year in both the text citation and reference entry. The letters follow the title order in the reference list. Keep both sources in your list here so the tool can calculate the letters together.
In-text citation and reference list examples
All sources below are fictional. Each short citation is paired with its full reference entry. The last pair uses two works by one author from the same year; the letters are generated from that pair, not typed into the source dates.
Book
- In-text citation
- (Quillmere 2025, 42)
- Reference entry
- Quillmere, Nella. 2025. Lantern Maps of Bellweather Quay. Mossglass Press.
Journal article
- In-text citation
- (Brindlewick 2025, 117)
- Reference entry
- Brindlewick, Oren. 2025. “Window Gardens Along the Larkmere Canal.” Journal of Imagined Neighborhoods 8 (2): 110–26. https://example.org/window-gardens.
Web page
- In-text citation
- (Quillmere 2025)
- Reference entry
- Quillmere, Nella. 2025. “Mapping the Footpaths of Bellweather Quay.” Bellweather Field Notebook, April 9. https://example.org/footpaths.
Newspaper article
- In-text citation
- (Valefern 2025)
- Reference entry
- Valefern, Tessa. 2025. “A New Ferry for Cloudmeadow.” Bellweather Imaginary Gazette, May 21. https://example.org/new-ferry.
No author
- In-text citation
- (Visitor Ledger 2025, 14)
- Reference entry
- A Visitor Ledger for Mossglass Pier. 2025. Pebble Lantern Press.
No date
- In-text citation
- (Reedwhistle Imaginary Archive, n.d.)
- Reference entry
- Reedwhistle Imaginary Archive. n.d. “The Reedwhistle Footbridge Register.” Accessed November 14, 2026. https://example.org/footbridges.
Same author, same year: Field Workbook
- In-text citation
- (Quillmere 2025a, 86)
- Reference entry
- Quillmere, Nella. 2025a. A Field Workbook for Cloudmeadow. 2nd ed. Mossglass Press.
Same author, same year: Lantern Maps
- In-text citation
- (Quillmere 2025b, 42)
- Reference entry
- Quillmere, Nella. 2025b. Lantern Maps of Bellweather Quay. Mossglass Press.
Match each citation to its reference
For the published sources shown here, the name or title and year in the text lead to the corresponding reference entry. The reference provides the rest of the publication details. Check that spelling and any year letters agree after you edit or delete a source.
Citing a paraphrase
Changing the wording does not remove the need to credit a borrowed idea. Cite the source of a paraphrase as well as a direct quotation. A page number helps readers locate a specific passage; use a locator the source actually provides, rather than inventing a page number for an unpaginated page.
Frequently asked questions
Does Chicago use in-text citations?
Yes, in the author-date system. The notes and bibliography system uses note numbers instead. Check which system your instructor requests.
How do I cite three or more authors?
In a Chicago 18 author-date text citation, use the first author’s surname followed by et al. Keep all authors in the source fields so the reference entry can be formatted separately.
What if a web page has no date?
Use n.d. in place of the year, with a comma before it, if no publication or revision date is available. Include an access date in the reference entry, or identify a dated archived version. Do not use the date you visited as a publication year.
Why did a or b appear after the year?
Those letters distinguish works by the same author from the same year. They must match in the text citation and reference list. Adding or removing a source can change the letters.