Style Guide Spelling Decisions

gray: Style Guide Spelling Decisions (AP, Chicago, MLA, APA)

How AP, Chicago, MLA, APA, and Merriam-Webster handle the spelling of "gray". American 'gray', British 'grey'. Both spellings appear in proper nouns (Earl Grey tea, Dorian Gray) regardless of dialect.

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 rulings on "gray"
Style guidePreferred form
AP Stylebook (2024–2025 Edition)gray
Chicago Manual of Stylegray
MLA Handbookgray
APA Publication Manualgray
Merriam-Webster Dictionarygray (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

In our own corpus the two forms are both common enough to rank: "gray" at #3,304 and "grey" at #3,105 by frequency, so "grey" is the more common spelling in written English and "gray" trails it by roughly 1.1x in rank position. That runs against the guides above, which lean toward "gray". A style ruling is a recommendation about what you should write, not a report of what people do write. Frequency rank is a corpus sample, not a vote, and it says nothing about which form is correct in your house style. Source: PlainSpell corpus, Wiktionary (kaikki.org) headwords with FrequencyWords 2018 English ranks

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.

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.

Last reviewed by the Plainspell Editorial team. See our methodology for how we source and verify style-guide rulings.