Title Case Rules: AP, APA, and Chicago Style Compared

5 min read

Title case means capitalizing the major words in a title or heading. But which words count as "major" depends on which style guide you follow. The three most common are AP (Associated Press), APA (American Psychological Association), and Chicago (The Chicago Manual of Style).

The Universal Rules

All three style guides agree on these basics:

  • Capitalize the first and last word, always
  • Capitalize nouns, verbs, adjectives, adverbs, and pronouns
  • Lowercase articles (a, an, the) unless they start the title
  • Lowercase coordinating conjunctions (and, but, or, nor, for, yet, so) unless they start the title

Where They Differ

RuleAP StyleAPA StyleChicago Style
PrepositionsLowercase if 3 letters or fewerLowercase if 3 letters or fewerLowercase all prepositions regardless of length
"With" (4 letters)CapitalizeCapitalizeLowercase
"Between" (7 letters)CapitalizeCapitalizeLowercase
Hyphenated compoundsCapitalize first elementCapitalize both elementsCapitalize both elements
"to" in infinitivesLowercaseLowercaseLowercase
Words after colonsCapitalizeCapitalizeCapitalize

Examples

StyleTitle
APThe Man Who Sold the World
APAThe Man Who Sold the World
ChicagoThe Man Who Sold the World
APRunning With Scissors
APARunning With Scissors
ChicagoRunning with Scissors

Words That Are Always Lowercase

Unless they are the first or last word of the title:

  • Articles: a, an, the
  • Coordinating conjunctions: and, but, or, nor, for, yet, so
  • Short prepositions (AP/APA): at, by, in, of, on, to, up
  • All prepositions (Chicago): at, by, in, of, on, to, up, with, from, into, between, through, etc.

Words That Are Always Capitalized

  • Verbs: Is, Are, Was, Be, Do, Has, Have (even short ones!)
  • Pronouns: It, He, She, We, They, My, Your
  • "Not": Always capitalized in all three styles

When to Use Which Style

ContextStyle Guide
News articles, journalismAP
Academic papers, researchAPA
Books, publishingChicago
Blog posts, web contentAP or Chicago (pick one, be consistent)

Convert to Title Case Instantly

Don't memorize the rules — use our case converter to automatically apply title case. You can also generate URL slugs from titles with the URL slug generator.