What is IEEE referencing?

IEEE is a numbered citation style used in engineering, computer science and related technical fields. You cite sources with numbers in square brackets, such as [1], in the order they first appear, and list the full references by number at the end.

Is the IEEE reference list alphabetical?

No. It is ordered by the number of first citation, so reference [1] is the first source cited in your text, [2] is the second and so on.

Can I reuse a number?

Yes. Once a source has a number, use the same number every time you cite it. Do not create a new entry for a source you already listed.

How do I cite several sources at once?

Give each number in its own brackets, such as [2], [5], or use a range for consecutive numbers, such as [3]-[6]. Check whether your course prefers one convention.

How many authors do I list?

IEEE guidance lists the authors' initials and surnames, and uses et al. for long author lists. Many guides use et al. when there are more than six authors, so check the guide your course follows.

IEEE Referencing: A Guide With Examples

If you study engineering, computer science, electronics or a related technical field, you will probably meet IEEE referencing. It looks different from the author-date styles used in the humanities and social sciences: the text is cleaner, with only numbers in square brackets, and all the detail lives in a numbered list at the end.

This guide explains how IEEE works, shows examples for the sources technical students cite most often and points out the mistakes that cost marks. The examples use invented sources to show the format. Departments sometimes add local rules, so check your course guide too.

How IEEE works

IEEE has two parts that must match:

In-text citations: a number in square brackets placed where you use a source, such as [1].
A reference list: entries numbered in the same order, listed at the end under the heading References.

Numbers are assigned in the order sources first appear in your text. The first source you cite is [1], the second is [2], and so on. If you cite [1] again later, you use the same number.

In-text citations

Basic pattern

Place the bracketed number before the punctuation of the sentence that uses the source.

Spaced sampling reduces aliasing in sensor networks [1].

You can also refer to the source in your sentence:

As shown in [2], latency increases sharply when the buffer is full.

Or name the author and keep the number: "Lee and Patel [3] demonstrated that..."

Several sources

Situation	Format
One source	[4]
Two or more separate sources	[4], [7]
A consecutive range	[4]-[7]
A specific page or section	[4, p. 12] or [4, Sec. 3]

Use the same format throughout the paper.

Citing the same source again

Reuse its original number. Do not add a new reference entry for a source already listed, and do not use "ibid." in IEEE.

The reference list

Title the list References.
Order the entries by number, not alphabetically.
Put the number in square brackets at the start of each entry.
Give authors' initials before surnames: J. Lee and R. Patel.
Use abbreviations for months and for journal titles, following standard practice.
Use sentence case for titles of articles in quotation marks, and italics for journal and book titles.

Examples

Journal article

Format: [n] A. A. Author, B. B. Author, "Title of article," Abbreviated Journal Title, vol. x, no. x, pp. xxx-xxx, Month Year, doi: xxx.

[1] J. Lee and R. Patel, "Adaptive sampling in wireless sensor networks," IEEE Trans. Sensor Syst., vol. 12, no. 3, pp. 210-224, Mar. 2021, doi: 10.0000/example.

Book

Format: [n] A. A. Author, Title of Book, edition. City, Country: Publisher, Year.

[2] M. Gomez, Embedded Systems Design, 2nd ed. Boston, MA, USA: Harbor Press, 2020.

Conference paper

[3] R. Patel and J. Lee, "Low-power scheduling for edge devices," in Proc. Int. Conf. Embedded Comput., Berlin, Germany, 2022, pp. 45-52.

Website

Format: [n] A. A. Author or Organization. "Title of page." Site name. URL (accessed Mon. DD, YYYY).

[4] National Standards Office. "Guidelines for sensor calibration." nso.example.org/calibration (accessed Mar. 12, 2025).

Standard or technical report

[5] Wireless Sensor Network Protocols, IEEE Standard 000.0, 2019.

[6] A. Author, "Title of report," Org. Name, City, Country, Rep. no., Year.

Dataset or software

[7] J. Lee, "Sensor dataset v1.2," 2023. [Online]. Available: https://data.example.org/sensors

Where a source type is not covered here, find the closest example in your course guide or the IEEE reference guide, and follow the same order of elements.

Formatting the paper

IEEE style is also associated with a particular layout, especially for papers submitted to IEEE conferences and journals, such as two-column text, numbered section headings and a specific abstract format. For a course assignment, follow your instructor's template. If none is given, a clean single-column layout with numbered headings is usually acceptable.

Equations, figures and tables are numbered and cited in the text, such as "Fig. 3" and "Table II." Captions for figures go below, and captions for tables go above.

Citing figures, tables and data

If you reuse a figure from a source, credit it in the caption and cite the source: "Fig. 2. Network topology. Adapted from [3]." If you create your own figure from published data, cite the data in the caption or text. Our guide on how to reference images, tables and figures covers the general principles.

Tools and checking

A reference manager such as Zotero can export IEEE style, which saves time. Check the output, because journal abbreviations, conference names and author lists often come through wrongly. Our citation generator can also build an entry to start from. Engineering and technical students can get an extra check on a finished list through citation and reference formatting.

Keeping numbers in order while you write

The most common IEEE headache is numbering. If you add a new source in the middle of a draft, every later number changes. Two habits prevent this.

Use a reference manager with a word processor plugin, which renumbers citations and rebuilds the list automatically when you insert or delete a source.
If you number by hand, write the citation as a short author-year placeholder while drafting, such as [Lee2021], and convert placeholders to numbers once the text is final.

Either way, finish by reading the paper from start to end and checking that the first bracketed number you meet is [1], the next new one is [2], and so on. If a number appears out of sequence, a source was added or moved after numbering.

Writing with citations in technical prose

Technical writing uses citations to separate established results from your own work. Cite when you state a known fact, use a method, compare with prior results or quote a figure. Do not cite for your own measurements or design decisions. A useful pattern is: cite the idea, say how your work differs, and then describe your contribution. For example, "Earlier schedulers reduce energy use by duty cycling [3], but they ignore link quality. We add a link-aware term..." This structure shows readers what is borrowed and what is new.

Common IEEE mistakes

Alphabetizing the list. It should follow citation order.
Numbering out of order. The first source cited must be [1].
Creating duplicate entries for the same source.
Forgetting the number in brackets or using parentheses.
Mixing author formats, such as surnames first.
Leaving out DOIs or access dates that the style asks for.
Citing in the text but missing from the list, or the other way around.
Using "ibid." where numbers should be reused.
Inconsistent abbreviations for journals and months.

IEEE compared with other numeric styles

IEEE is one of several numeric styles. Vancouver, used in medicine and health sciences, is also numbered but formats authors and journals differently. Our guide to Vancouver referencing shows the contrast. Author-date styles such as APA and Harvard put the author and year in the text, which means a reader can see the source without looking at the list.

Feature	IEEE	Vancouver	APA 7
In-text	[1]	(1) or superscript	(Author, 2020)
List order	Order of citation	Order of citation	Alphabetical
Author format	J. Lee	Lee J	Lee, J.
Typical fields	Engineering, computing	Medicine, health	Social sciences, education

A quick checklist

Are in-text numbers in square brackets and in order of first citation?
Does the list follow the same order?
Does each entry match the right source type?
Are authors, titles, dates, volumes and pages correct?
Have I used consistent abbreviations?
Is every source in the text in the list, and the reverse?

Final thoughts

IEEE is among the simplest styles once you understand its logic: number sources as you meet them, reuse the number when you cite the same source again and give the full details in the list. Keep a running list as you write, so numbers never get out of order, and check the finished list against your sources one by one.