Which Words in a Title Should Be Capitalized?

There is no single set of rules for capitalizing words in a title of a book, article, essay, movie, song, poem, play, television program, or computer game. And, unfortunately, even style guides disagree, complicating matters.

However, here is a basic guide to the two most common methods, sentence case and title case, and the top differences between some of the main title capitalization styles. For most of us, it's a matter of selecting one convention and sticking to it.

First, which is which?

Sentence Case (Down Style) or Title Case (Up Style)

In sentence case, which is the simplest, titles are treated more like sentences: You capitalize the first word of the title and any proper nouns (not the same for subtitles).

In title case, on the other hand, which is the most prevalent in book titles and magazine and newspaper headlines, you capitalize the first and last words of the title and all nouns, pronouns, adjectives, verbs, adverbs, and subordinating conjunctions (if, because, as, that, and so on). In other words, all the important words.

But this is where things start getting sticky. There are four main title capitalization styles: Chicago style (from the style manual published by the University of Chicago), APA style (from the American Psychological Association), AP style (from The Associated Press), and the MLA style (from the Modern Language Association).

In American mainstream publishing, Chicago and AP are the most widely used and referenced (APA and MLA are more used in scholarly articles). And when it comes to capitalization, it's the little words that they disagree on.

Little Words

According to "The Chicago Manual of Style," "articles (a, an, the), coordinating conjunctions (and, but, or, for, nor), and prepositions, regardless of length, are lowercased unless they are the first or last word of the title."

"The Associated Press Stylebook" is fussier. It calls for:

• Capitalizing the principal words, including prepositions and conjunctions of three or more letters
• Capitalizing an article—the, a, an—or words of fewer than four letters if it is the first or last word in a title

Other guides say that prepositions and conjunctions of fewer than five letters should be in lowercase—except at the beginning or end of a title. (For additional guidelines, see the glossary entry for title case.)

"Whichever preposition rule you adopt, you need to remember that many common prepositions [can also] function as nouns, adjectives, or adverbs, and when they do, they should be capitalized in a title," says Amy Einsohn in her "Copyeditor's Handbook."

A Capital Answer

So, should you use sentence case or title case?

If your school, college, or business has a house style guide, that decision has been made for you. If not, simply pick one or the other (flip a coin if you have to), and then try to be consistent.

A note on hyphenated compound words in a headline: As a general rule, says the latest edition of "The New York Times Manual of Style and Usage" (that newspaper's style manual), "capitalize both parts of a hyphenated compound in a headline: Cease-Fire; Able-Bodied; Sit-In; Make-Believe; One-Fifth. When a hyphen is used with a prefix of two or three letters merely to separate doubled vowels or to clarify pronunciation, lowercase after the hyphen: Co-op; Re-entry; Pre-empt. But: Re-Sign; Co-Author. With a prefix of four letters or more, capitalize after the hyphen: Anti-Intellectual; Post-Mortem. In sums of money: $7 Million; $34 Billion."

One piece of advice on this subject comes from "The Chicago Manual of Style:" "Break a rule when it doesn't work."

And if you want a little help, there are sites online that will check your titles for you.