Is "Of" Capitalized in a Title?

Title capitalization guide

No in most style guides — "of" is lowercase in AP Style, Chicago Style, and MLA Style.

preposition

Capitalized in 2 styles

Lowercase in 8 styles

Title Case

Lowercase as a short preposition unless first or last word

AP Style

Lowercase — AP lowercases all prepositions

NYT Style

YES

Capitalized — NYT Style capitalizes prepositions

Chicago Style

Lowercase — two letters, well under the four-letter threshold

MLA Style

Lowercase as a short preposition

APA Style

Sentence case — only first word and proper nouns

AMA Style

Lowercase — AMA follows AP-style rules

BB Style

YES

Every word capitalized — no exceptions

Wikipedia Style

Sentence case — only first word and proper nouns

Sentence Case

Only the first word of a title is capitalized

The full answer

"Of" appears in a vast number of titles and is one of the words most frequently lowercased in standard title case. It is lowercase in AP Style, Chicago Style, MLA Style, and AMA Style, but capitalized in NYT Style.

"Of" appears in many famous titles — "The Sound of Music," "Lord of the Flies," "The Heart of Darkness" — and is consistently lowercase in the published versions because book publishers follow Chicago Style.

The NYT Style capitalization of "of" is one of the reasons NYT headlines look visually bolder than AP-style headlines. More words capitalized per line creates a denser, more emphatic appearance.

"Of" that opens or closes a title is always capitalized regardless of style. A title like "Of Mice and Men" capitalizes "Of" because it is the first word, not because of any preposition rule.

"Of" is two letters long and functions almost exclusively as a preposition. AP Style, Chicago Style, MLA Style, and AMA Style all lowercase it consistently. The only mainstream style that capitalizes it in the middle of a title is NYT Style.