“Gray” is the usual US spelling and “grey” is the usual UK spelling of the same color word. “Grey” also occurs in Canadian and other varieties; follow the target regional or house style rather than treating one form as globally wrong.
ReviewedEvidence2 sourcesSectionEnglish Usage
Quick answer
“Gray” is the usual US spelling and “grey” is the usual UK spelling of the same color word.
Key details
Confusion Familyregional-spelling
Noun Variant Scope“Grey” also occurs in Canadian and other varieties; follow the target regional or house style rather than treating one form as globally wrong.
Rule Familyregional-orthography
Termsgray, grey
Further guidance
Core difference
“Gray” is the usual US spelling and “grey” is the usual UK spelling of the same color word.
Fast Test
Choose the form that matches the intended meaning, grammatical role, and documented regional convention; do not treat a standard regional variant as an error.
Variant Boundary
“Grey” also occurs in Canadian and other varieties; follow the target regional or house style rather than treating one form as globally wrong.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
“Aging” and “ageing” are established regional spellings. Cambridge labels aging as US and ageing as UK, so the choice should follow the intended variety or house style.
“Analyze” is the standard US spelling and “analyse” is the standard UK spelling of the same verb. The distinction is regional spelling; use the form that matches the target variety or editorial style.
“Behavior” is the US spelling and “behaviour” is the UK spelling. Use the form consistent with the regional variety or editorial style of the document.
Both “canceled” and “cancelled” are standard past-tense spellings of “cancel”; US English usually uses one l, while UK English normally uses two. Cambridge records the -ll- forms and notes that US English usually uses -l-, so the difference should be presented as a regional preference rather than a correctness split.
