ACS Format Citation: Rules, Examples & Generator
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0 sourcesACS Format Citation is the American Chemical Society style used in chemistry. References are numbered in citation order and cited in text with superscript numbers. A journal reference lists authors, article title, abbreviated journal name in italics, bold year, italic volume, pages, and DOI.
What is ACS citation style?
ACS citation style is the referencing system of the American Chemical Society, used across chemistry and allied sciences. It pairs in-text markers with a numbered reference list, letting readers trace claims to sources without breaking the flow of dense technical prose.
ACS supports three in-text systems: superscript numbers, italic numbers in parentheses, and author–date names. The numeric systems are the most common. In both numeric systems, the reference list is numbered in the order sources first appear in the text, not alphabetically. Individual ACS journals publish their own tweaks, so always check the target journal’s author guidelines.
How do you format an ACS reference?
An ACS journal reference gives the author names first, then the article title, the abbreviated journal name in italics, a bold year, an italic volume, the issue and page range, and the DOI. Semicolons separate multiple authors, and no “and” precedes the final author.
- Authors — surname then initials with periods; separate each author with a semicolon, no “and.”
- Article title — in sentence case, ending with a period; some journals omit titles.
- Journal — CASSI abbreviation, italicized, with periods on abbreviated words.
- Year, volume, issue, pages — year in bold, volume in italics, issue in parentheses, page range.
- DOI — full
https://doi.org/link, closing the reference with a period.
| Element | ACS rule |
|---|---|
| Author names | Surname, First initial. Middle initial.; list all, separated by semicolons |
| Year | Bold, placed after the journal abbreviation |
| Volume | Italic, followed by the issue in parentheses |
| Journal name | Abbreviated (CASSI) and italicized |
| Order in list | Numbered by first appearance in the text |
How do you cite sources in text in ACS?
In ACS numeric style you flag each source with a superscript number placed after the relevant word or punctuation, or with an italic number in parentheses. The number matches the entry in the numbered reference list. Reuse the same number every time you cite that source again.
- Superscript: Copper catalysts show high selectivity for CO2 reduction.1
- Italic in parentheses: Copper catalysts show high selectivity for CO2 reduction (1).
- Multiple sources: Several groups report similar yields.2,4,7 or a range.2–5
- Author–date option: This trend was first reported by Nakamura and Patel (2019).
Place superscript numbers outside commas and periods but inside colons and semicolons. When you name the author in a sentence, the citation number still appears at the reference point, keeping the reference list unambiguous.
ACS reference examples by source type
The pattern shifts with the source: books add edition and publisher, chapters add the editor and “In,” and theses name the degree and institution. The examples below are copy-ready templates you can adapt with real details.
Journal articleWang, Y.; Patel, S. K.; Nakamura, H. Selective Hydrogenation of Alkynes over Palladium Nanoparticles. J. Am. Chem. Soc. 2021, 143 (12), 4567–4575. https://doi.org/10.1021/jacs.1c00456.
BookAtkins, P.; de Paula, J. Physical Chemistry, 10th ed.; Oxford University Press: Oxford, U.K., 2014.
Book chapterSmith, R. L. Reaction Mechanisms in Organometallic Systems. In Advances in Organic Synthesis; Kumar, A., Ed.; Elsevier: Amsterdam, 2019; Vol. 3, pp 112–140.
ThesisOkonkwo, C. A. Synthesis of Chiral Ligands for Asymmetric Catalysis. Ph.D. Dissertation, University of Michigan, Ann Arbor, MI, 2020.
PatentRivera, D. M.; Hassan, T. Process for Producing Lithium Iron Phosphate. U.S. Patent 10,987,654 B2, April 20, 2021.
How do you cite a website in ACS?
An ACS website reference gives the author or organization, the title of the page, the full URL, and an access date in year-month-day format inside parentheses. When a corporate body is the author, use its name in the author position rather than repeating it as publisher.
WebsiteNational Institute of Standards and Technology. NIST Chemistry WebBook. https://webbook.nist.gov/chemistry/ (accessed 2023-09-15).
Web articleFernández, L. Green Solvents Gain Ground in Industry. Chemical & Engineering News. https://cen.acs.org/environment/green-solvents (accessed 2023-11-02).
The (accessed YYYY-MM-DD) element is essential because web content changes; it records the version you consulted. If the page carries a publication or revision date, include it before the URL so readers can judge currency.
How accurate is ACS formatting, and what are the limits?
ACS rules are precise but not fully uniform. The ACS Guide to Scholarly Communication sets defaults, yet each society journal can override them, so the “correct” format depends on where you submit. Treat generated citations as a strong first draft, then verify against your journal’s guidelines.
- Journal abbreviations vary: ACS uses CASSI abbreviations; automated tools sometimes output the full title. Confirm each abbreviation.
- Titles are optional: some ACS journals omit article titles entirely to save space, so check before including them.
- Author limits differ: the default lists all authors, but some journals truncate long lists with “et al.” after ten names.
- Numbering must stay in order: if you reorder text, renumber the reference list so it still follows first appearance.
No generator can read a specific journal’s house style for you. Always cross-check DOIs, page ranges, and italics/bold formatting against the original source before submission.
ACS citation FAQ
Common questions about ACS format citation, answered concisely.
Is the ACS reference list alphabetical?
No. In the numeric systems, ACS references are numbered and listed in the order sources first appear in the text. Only the author–date variant arranges entries alphabetically by surname.
Are article titles required in ACS style?
The current ACS Guide recommends including article titles, but many ACS journals omit them to save space. Check your target journal’s author guidelines before deciding whether to keep the title.
What goes in bold and italics in an ACS reference?
The publication year is bold, and the volume number and journal abbreviation are italicized. Book and periodical titles are also italicized; article titles stay in regular roman type.
How do I cite multiple sources at once in ACS?
List the numbers together, separated by commas with no spaces, using an en dash for consecutive runs: superscript 2,4,7 for separate sources or 2–5 for a continuous range.
Does ACS use “and” before the last author?
No. ACS separates every author with a semicolon and does not insert “and” before the final name. Each author appears as surname followed by initials with periods.
What date format does ACS use for websites?
ACS uses year-month-day for access dates, written as (accessed 2023-09-15). Place it in parentheses immediately after the URL that ends the reference.