Title Case Rules: AP, APA, Chicago & MLA Style Guide

Title case is the capitalization style used for headings, titles, and headlines. But the rules aren't as simple as "capitalize every word." Different style guides have different rules about which words to capitalize and which to leave lowercase. This guide covers the four major style guides so you never second-guess a title again.

The Universal Rules

All major style guides agree on these basics:

• Always capitalize the first and last words of the title
• Always capitalize nouns, pronouns, verbs, adjectives, and adverbs
• Do not capitalize short conjunctions (and, but, or, nor, for, yet, so)
• Do not capitalize short prepositions (in, on, at, to, by, for, of, up)
• Do not capitalize articles (a, an, the) — unless they are the first or last word

Style Guide Differences

AP Style Title Case

The Associated Press style is used by journalists and news organizations. Its key rule: capitalize all words with four or more letters, regardless of part of speech. This means words like "with," "from," and "into" are capitalized in AP style but not in Chicago style.

APA Style Title Case

The American Psychological Association style, used in academic and scientific papers, follows rules similar to AP. Capitalize all words with four or more letters, all major words, and both words in a hyphenated compound. Use our APA Format Converter to apply these rules automatically.

Common Mistakes to Avoid

• Capitalizing "a," "an," "the" in the middle: These articles stay lowercase unless they start the title.
• Lowercasing short verbs: Words like "is," "am," "be," "do," and "go" are verbs and must be capitalized, even though they are short.
• Forgetting the last word: The last word is always capitalized, even if it is an article or preposition.
• Inconsistent hyphenation: In most styles, capitalize both parts of a hyphenated word in a title (e.g., "Self-Driving" not "Self-driving").

Automate Title Case Conversion

Remembering all these rules is hard. The easiest approach is to use an automated tool:

• Smart Title Case — Applies intelligent title case rules, handling articles, prepositions, and conjunctions correctly
• Simple Title Case — Capitalizes the first letter of every word (simpler but less accurate)
• Sentence Case — Capitalizes only the first word of each sentence

For academic papers following APA guidelines, use the dedicated APA Format Converter to get perfectly formatted titles every time.