How major style guides rule on "gray"
American 'gray', British 'grey'. Both spellings appear in proper nouns (Earl Grey tea, Dorian Gray) regardless of dialect.
The disagreement on "gray" is an example of systematic American vs British English differences, the category of style-guide differences that most often confuses copy editors and creates inconsistency across long documents. Below is a guide-by-guide breakdown, drawn directly from the published editions cited.
| Style guide | Preferred form |
|---|---|
| AP Stylebook (2024–2025 Edition) | gray |
| Chicago Manual of Style | gray |
| MLA Handbook | gray |
| APA Publication Manual | gray |
| Merriam-Webster Dictionary | gray (also grey) |
What the divergence actually means
Unlike many compound-modernization decisions where style guides eventually converge, "gray" continues to show genuine divergence between major guides. The AP Stylebook treats this as a settled call; Chicago Manual leaves more flexibility; and Merriam-Webster, as a descriptive dictionary, records both forms. Source: Chicago Manual of Style, 17th Edition
The APA Publication Manual aligns with AP and Chicago on "gray", though APA generally addresses spelling questions only when they intersect with statistical reporting or technical psychology vocabulary. Where the manual is silent, APA defers to Merriam-Webster as its standard reference. Source: APA Publication Manual, 7th Edition
Merriam-Webster lists "gray (also grey)", which serves as the lexicographic baseline for U.S. style decisions. Because Merriam-Webster's entries reflect aggregated published usage rather than editorial preference, when a guide says "follow Merriam-Webster", as APA does, that effectively delegates the call to whichever spelling has dominated the published corpus. Source: Merriam-Webster Dictionary
Garner's Modern English Usage classifies the "gray" / "grey" pair on its Language-Change Index, a five-stage scale measuring whether a once-disputed form has been accepted into Standard English. For systematic American vs British English differences, Garner's typically rates the dominant form at Stage 4 ("ubiquitous but objected to by traditionalists") or Stage 5 ("fully accepted"). Source: Garner's Modern English Usage, 5th Edition
Practical guidance for editors
For working writers, the practical rule is straightforward: in journalism, follow AP; in academic writing in the humanities, follow MLA or Chicago; in social-science publishing, follow APA; in book publishing, follow Chicago. When no house style applies, Merriam-Webster's main entry is the safest default. The differences across these guides on "gray" reflect not disagreement about correctness but different audiences and editorial pressures.
Editorial context
In web development and computing standards, 'grey' persists as a fully interchangeable alternative to 'gray' for the CSS color keyword representing #808080, a deliberate design choice in specifications like CSS Level 1 (1996) to accommodate both American and British English without functional disparity. This equivalence, maintained through current W3C modules, allows code like div { background-color: grey; } to render identically across browsers and regions, prioritizing interoperability over spelling orthodoxy. Such technical bipartisanship reveals a pragmatic register split absent from the formal style consensus in U.S. publishing, where 'gray' dominates prose; yet it ensures 'grey' endures in global digital contexts, from UI design to data visualization tools, reflecting how industry needs can preserve dual forms long after regional norms solidified.
Cross-references
For the dictionary entry, frequency data, and pronunciation of gray, see the main word page. For other style-guide spelling decisions in this category, browse all style-guide spelling rulings.