IEEE style is the standard citation format for electrical engineering, computer science, and most other technical and engineering fields. Unlike author-date styles like APA, IEEE uses a numbered system — which makes it fast to read in-text, but strict about how the reference list itself has to be built and ordered. Here’s how the mechanics work. For a full comparison against APA, MLA, Chicago, Harvard, and Vancouver, see our complete citation styles guide.
In-Text Citations: Numbered, in Order of Appearance
- Each source gets a number in square brackets the first time it’s cited: [1], [2], [3]…
- That same number is reused every time the source is cited again later in the paper — sources are not renumbered each time, and they’re not alphabetical.
- Multiple sources cited together: [1], [3] or [1]–[3] for a consecutive range.
- The number refers to the whole source, not a specific page — if you need to point to a specific page, IEEE allows adding it after the number: [4, p. 12].
- IEEE citation numbers are typically treated as nouns, not adjectives — write “as shown in [3],” not “as shown in reference [3]” (though conventions vary slightly by publisher, so check your target journal’s specific examples).
The Reference List Order
This is the biggest structural difference from author-date styles: the IEEE reference list is ordered by citation number (the order sources first appear in the text), not alphabetically by author surname. Reference [1] in your reference list is whichever source you cited first in the body of the paper — even if its author’s last name starts with “Z.” This means that if you add a new citation early in your paper during revision, every subsequent reference number may need to shift — a detail that’s easy to get wrong when editing by hand, and one of the strongest arguments for using a citation manager that renumbers automatically.
Formatting Common Source Types
- Journal article: [1] A. Chen and B. Patel, “Title of the article in sentence case,” Abbreviated Journal Name, vol. 12, no. 3, pp. 40–55, Mar. 2021.
- Conference paper: [2] A. Chen, “Title of the paper,” in Proc. Conference Name, City, Country, 2021, pp. 100–110.
- Book: [3] A. Chen, Title of the Book, 2nd ed. City: Publisher, 2020.
- Website: [4] A. Chen. “Title of the page.” Organization. Accessed: Mon. Day, Year. [Online]. Available: URL
- Standard: [5] IEEE Standard for [Title], IEEE Std XXX-YYYY, Year.
- Thesis or dissertation: [6] A. Chen, “Title of thesis,” M.S. thesis, Dept., University, City, Year.
Notice that IEEE uses author initials before the last name (“A. Chen,” not “Chen, A.”), sentence case for article titles, and journal/publisher abbreviations where standard ones exist — all details that differ from APA and MLA.
Citing Sources With Multiple Authors
For up to six authors, list all of them: A. Chen, B. Patel, and C. Osei. For more than six, IEEE allows “et al.” after the first author’s name, though check your specific journal or conference’s preference, since some technical publishers set their own threshold.
Common IEEE Mistakes
- Alphabetizing the reference list instead of ordering it by citation number
- Renumbering a source each time it’s cited, instead of reusing its original number throughout the paper
- Using title case instead of sentence case for article titles
- Formatting author names in “Last, First” order instead of IEEE’s “First Initial. Last” order
- Missing volume, issue, or page number details that IEEE requires but other styles sometimes treat as optional
- Forgetting to update every reference number after inserting a new citation earlier in the document during revision
Frequently Asked Questions
Does IEEE style differ between IEEE journals and IEEE conference papers? The core numbering system stays the same, but small formatting details (like abbreviations for conference proceedings vs. journal names) can differ — always check the specific publication’s template.
Can I use a citation manager for IEEE style? Yes — Zotero, Mendeley, and EndNote all include an IEEE output style, which handles the numbering and reordering automatically as you add or remove citations, though it’s still worth spot-checking a few entries against the rules above.
Keeping citation numbers, their order, and every reference entry’s formatting consistent across a long technical paper is detail work that’s easy to get slightly wrong, especially after several rounds of edits reorder your citations. Our reference and citation formatting service checks and corrects IEEE references alongside every other major style. Get in touch if you’d like a check before you submit.