Title case is a capitalisation style for headings and titles in which the first and last words plus all the important content words are capitalised, while minor words stay lowercase. The content words that get capitalised are nouns, pronouns, verbs, adjectives, and adverbs. The minor words that stay lowercase are articles (a, an, the), coordinating conjunctions (and, but, or), and short prepositions (of, in, to, at). For example, "the lord of the rings" becomes "The Lord of the Rings" — "of" and the second "the" stay down, but the first "The" is capitalised because it starts the title.
The catch is that the exact rules differ between style guides, so the "correct" title case depends on which one you follow:
- Chicago and APA lowercase prepositions of three letters or fewer but capitalise longer ones ("Between", "Through").
- AP style capitalises all words of four or more letters, and capitalises prepositions of four+ letters regardless of role.
- Most guides capitalise both parts of a hyphenated compound in a title ("Well-Being").
Title case is standard for book and article titles, headlines, and often product names and navigation labels, where it signals formality and importance. Its counterpart is sentence case, which capitalises only the first word and proper nouns and is increasingly preferred for UI and modern editorial voice. A common mistake is capitalising every word including "the" and "of" — that is not title case, it is "start case". Because deciding which words to lowercase is fiddly and guide-dependent, it is easy to get wrong by hand; convert text reliably with our letter case converter.