Title Case Rules: AP, APA, MLA & Chicago Explained

If you have ever stared at a title and wondered whether “with” should be “With” or “with,” you have run into one of the most quietly confusing corners of English writing. Title case looks simple — capitalize the important words — but AP, APA, MLA, and Chicago disagree on which words count as important, so the same title can be correctly capitalized four different ways.

This guide explains all four sets of title case rules side by side, with examples, a comparison table, and the tricky cases: short prepositions, hyphenated words, subtitles after colons, and case converter mistakes.

What Is Title Case?

Title case is a style of capitalization used for titles of books, articles, essays, headlines, songs, and other works. In title case, most words are capitalized, but a small set of “minor” words — articles, short prepositions, and short conjunctions — are left lowercase.

That last point separates true title case from simply capitalizing every word. Capitalizing every single word, including “and,” “the,” and “of,” is sometimes called “start case” — it is not title case under any major style guide. For example:

Start case (incorrect as title case): “The Old Man And The Sea”
Title case (correct): “The Old Man and the Sea”

Title case is a deliberate system: it signals that the writer knows the conventions of the publication they are writing for.

Title Case vs Sentence Case

The main alternative to title case is sentence case. In sentence case, only the first word of the title and any proper nouns are capitalized — exactly as in an ordinary sentence.

Title case: “How to Write a Cover Letter That Gets Read”
Sentence case: “How to write a cover letter that gets read”

Neither style is more correct in the abstract — what matters is which one your audience, publication, or style guide expects:

Context	Usual style
Book titles	Title case
Academic paper titles (APA, MLA, Chicago)	Title case
Article titles in APA reference lists	Sentence case
Article titles in MLA Works Cited lists	Title case
News headlines (US newspapers)	Title case (varies by outlet)
News headlines (BBC, many digital outlets)	Sentence case
Blog post titles	Either — but be consistent
YouTube video titles	Creator’s choice — be consistent
Email subject lines	Usually sentence case

The APA distinction catches many students out: your own paper’s title uses title case, but a journal article’s title in your reference list uses sentence case, while the journal’s name stays in title case. Getting this backwards is one of the most common APA formatting errors.

Sentence case has one clear advantage: there is almost nothing to decide.

The Rules All Four Guides Agree On

AP, APA, MLA, and Chicago all agree on these points:

Capitalize the first word of the title, no matter what it is. Even an article or short preposition is capitalized at the start. “The” at the start of a title is always “The.”
Capitalize the last word of the title, no matter what it is. In “The World We Live In,” the final “In” is capitalized under all four guides.
Capitalize proper nouns and proper adjectives always. Names of people, places, organizations, and brands keep their capitals wherever they appear, including unusual forms such as iPhone or eBay.
Capitalize the first word of a subtitle. When a title has a colon, the first word after the colon is capitalized under all four guides. In “On Writing: A Memoir of the Craft,” the “A” after the colon is capitalized even though “a” is an article.
Capitalize verbs, including short ones. “Is,” “Be,” “Am,” and “Are” are verbs, so they are capitalized in title case even though they are short. Lowercasing “is” because it is small is a frequent error.
Lowercase “to” when it is part of an infinitive. In “What to Do About It,” the “to” before “Do” is lowercase under all four guides, because it belongs to the infinitive verb form.

With that common ground in place, the guides diverge on one central question: what counts as a “minor” word?

AP Style Title Case Rules

The Associated Press (AP) stylebook governs most American newsrooms, and its title case rules are built around word length.

The AP rule: Capitalize all words except articles (a, an, the), prepositions of fewer than four letters, and conjunctions of fewer than four letters. Capitalize prepositions and conjunctions of four or more letters. Always capitalize the first and last words.

In practice: capitalize nouns, pronouns, verbs, adjectives, adverbs, and any preposition or conjunction with four or more letters. Lowercase “a,” “an,” “the,” short prepositions such as “of,” “to,” “in,” “on,” “at,” “by,” and “for,” and short conjunctions such as “and,” “but,” “or,” “nor,” and “yet.” Long prepositions and conjunctions — “Through,” “Between,” “With,” “From,” “About,” “Although” — are capitalized.

Examples in AP title case:

“A Journey Through the Night” — “Through” is capitalized because it has seven letters.
“The Girl Who Played With Fire” — “With” is capitalized because it has four letters.
“Love in the Time of Cholera” — “in” and “of” stay lowercase because they are short.

The AP rule is easy to apply: count the letters. Four or more, capitalize it; fewer than four, lowercase it (for prepositions and conjunctions). Articles are lowercase except as the first or last word.

APA Style Title Case Rules

The American Psychological Association (APA) style, used across the social sciences, is very close to AP, but its rule has a slightly different cutoff.

The APA rule: Capitalize major words, defined as nouns, verbs, adjectives, adverbs, and pronouns, plus any word of four or more letters. Lowercase minor words of three or fewer letters: articles, short prepositions, and short conjunctions. Always capitalize the first word, the last word, and the first word after a colon or em dash.

In effect, APA and AP agree on most titles. The differences show up in edge cases: APA also capitalizes the first word after an em dash, and it capitalizes verbs of any length, including “Is” and “Be.”

Examples in APA title case:

“A Journey Through the Night” — identical to AP, since “Through” has more than three letters.
“The Girl Who Played With Fire” — “With” is capitalized, again matching AP.
“What If We Tried a Different Approach” — APA lowercases the short conjunction “If” by the letter-count rule, while MLA and Chicago would capitalize it as a subordinating conjunction. This is one of the few places where APA visibly differs from MLA and Chicago.
“Learning to Read in a Digital Age” — “to” in the infinitive is lowercase, “in” is lowercase, and “a” is lowercase.

Remember the APA reference-list exception: this rule applies to your own paper’s title and to journal names, but article titles inside reference entries switch to sentence case — the most common source of APA title mistakes.

MLA Style Title Case Rules

The Modern Language Association (MLA) style, used widely in the humanities, uses no letter-count rule at all. Instead, it classifies words by their part of speech.

The MLA rule: Capitalize the first and last words and all principal words: nouns, pronouns, verbs, adjectives, adverbs, and subordinating conjunctions. Lowercase articles, prepositions, coordinating conjunctions, and the “to” in infinitives — regardless of how long the word is.

That last phrase is the key difference. In MLA, a preposition stays lowercase even if it is long:

“A Journey through the Night” — “through” is lowercase in MLA, even though it has seven letters. AP and APA would capitalize it.
“The Girl Who Played with Fire” — “with” is lowercase in MLA. This is the form you will see on the actual book cover.
“The House Between Two Worlds” — “Between” is lowercase in MLA, capitalized in AP and APA.

But MLA capitalizes subordinating conjunctions regardless of length, because they are principal words:

“What If We Tried a Different Approach” — “If” is capitalized in MLA, because it is a subordinating conjunction. AP and APA lowercase it.

MLA’s logic is worth internalizing: ask what job the word does in the sentence, not how many letters it has. Prepositions and coordinating conjunctions are supporting words, so they stay small; subordinating conjunctions introduce clauses, so they count as principal words.

Chicago Style Title Case Rules

The Chicago Manual of Style (CMOS), the standard for most American book publishing, has headline-style capitalization close to MLA — with its own important details.

The Chicago rule: Capitalize the first and last words, all nouns, pronouns, adjectives, verbs, adverbs, and subordinating conjunctions. Lowercase articles, coordinating conjunctions, and prepositions — regardless of length — except when a preposition is used adverbially or adjectivally, or when it is part of a phrasal verb.

In practice, Chicago matches MLA on the headline cases: “A Journey through the Night,” “The Girl Who Played with Fire,” and “What If We Tried a Different Approach.”

Where Chicago stands apart is the adverbial and phrasal-verb exception. When a word that looks like a preposition is actually functioning as an adverb or as the particle of a phrasal verb, Chicago capitalizes it:

“Run Up the Score” — “Up” is capitalized because it is the particle of the phrasal verb “run up,” not a preposition indicating direction.
“Look Out for Trouble” — “Out” is capitalized for the same reason.

Chicago also capitalizes the first word after a colon in a subtitle. The real fault line runs between the length-based guides (AP and APA) and the word-class guides (MLA and Chicago) — and since Chicago and MLA agree on most titles, learning one takes you most of the way to the other.

Side-by-Side Comparison: The Same Titles in All Four Styles

The fastest way to see the differences is to put the same titles through all four guides:

Original title idea	AP	APA	MLA	Chicago
A journey through the night	A Journey Through the Night	A Journey Through the Night	A Journey through the Night	A Journey through the Night
The girl who played with fire	The Girl Who Played With Fire	The Girl Who Played With Fire	The Girl Who Played with Fire	The Girl Who Played with Fire
Love in the time of cholera	Love in the Time of Cholera	Love in the Time of Cholera	Love in the Time of Cholera	Love in the Time of Cholera
What if we tried a different approach	What if We Tried a Different Approach	What if We Tried a Different Approach	What If We Tried a Different Approach	What If We Tried a Different Approach
The house between two worlds	The House Between Two Worlds	The House Between Two Worlds	The House between Two Worlds	The House between Two Worlds
The world we live in	The World We Live In	The World We Live In	The World We Live In	The World We Live In
On writing: a memoir of the craft	On Writing: A Memoir of the Craft	On Writing: A Memoir of the Craft	On Writing: A Memoir of the Craft	On Writing: A Memoir of the Craft
The art of war: strategies for modern life	The Art of War: Strategies for Modern Life	The Art of War: Strategies for Modern Life	The Art of War: Strategies for Modern Life	The Art of War: Strategies for Modern Life

Three patterns jump out:

First, most titles are identical across all four guides. Short prepositions, articles, and ordinary nouns and verbs are treated the same everywhere — without long prepositions or short subordinating conjunctions, the guide you pick barely matters.

Second, long prepositions are the main fault line. “Through,” “With,” and “Between” split the guides cleanly: AP and APA capitalize them for their length, while MLA and Chicago lowercase them for their word class. If you remember only one difference, make it this one.

Third, short subordinating conjunctions split the guides in the opposite direction. “If” is lowercase in AP and APA because it is short, but capitalized in MLA and Chicago because it is a subordinating conjunction. Also note where all four guides agree despite tricky words: “The World We Live In” capitalizes the final “In” everywhere (the first-and-last-word rule overrides everything else), and the subtitle rows capitalize “A” after the colon everywhere (the first-word-of-subtitle rule overrides the article rule).

Tricky Words: Articles, Prepositions, Conjunctions, and Hyphenated Words

Articles: a, an, the

Articles are lowercase mid-title under all four guides, capitalized only as the first word, the last word (rare), or the first word of a subtitle — “The Old Man and the Sea” capitalizes “The” because it is the first word.

One exception: keep “The” capitalized when it is part of a proper name. “The Beatles” and “The New York Times” keep their capital “T” even mid-title, because the “The” belongs to the name itself — in “The Music of The Beatles,” the second “The” stays capitalized, while a plain article would be lowercase.

Prepositions: the length trap

Prepositions cause more title case errors than any other word class, because the guides genuinely disagree about them. Decide your guide first, then apply its rule:

AP and APA: Count the letters — four or more means capitalize, fewer means lowercase. “Through,” “Between,” “With,” “From,” “About,” and “Under” are capitalized; “Of,” “In,” “On,” “At,” “By,” “To,” and “For” are lowercase.
MLA and Chicago: Do not count letters. All prepositions are lowercase, no matter how long, unless first or last word, first word of a subtitle, or (Chicago only) adverbial or part of a phrasal verb.

Note that “over” and “under” can also function as adverbs, which is where Chicago’s exception comes in. In “The Plane Flew Over the City,” “Over” is a preposition and stays lowercase in Chicago; in “Tide Over Troubled Times,” “Over” is part of the verb phrase, so Chicago capitalizes it. Unsure? Try removing the word: if the sentence still makes sense, it was probably a preposition; if the meaning collapses, it was part of the verb.

Conjunctions: coordinating vs subordinating

Coordinating conjunctions join equal elements: and, but, or, nor, for, so, yet. These are lowercase mid-title under all four guides, because they are all short and all coordinating.

Subordinating conjunctions introduce dependent clauses: because, although, when, while, if, as, since, unless, until. Here the guides split. AP and APA apply the length rule: “Because” and “Although” are capitalized as long words, while short ones such as “if” and “as” are lowercase. MLA and Chicago capitalize all subordinating conjunctions as principal words, regardless of length.

The word “as” deserves a warning: it can be a preposition (“dressed as a teacher”) or a conjunction (“as I was saying”), and its treatment follows its function — capitalized in MLA and Chicago as a conjunction, lowercase in AP and APA, and handled as a preposition otherwise.

Hyphenated words

Hyphenated compounds follow a consistent logic across the guides:

Capitalize the first element always. “Well-Known,” “Up-to-Date,” and “E-Commerce” all capitalize their first part.
Capitalize the second element if it is a principal word. “Well-Known” capitalizes “Known” because it is an adjective. “Follow-Up” capitalizes “Up” in the noun sense.
Lowercase the second element if it is a minor word. “Up-to-Date” keeps “to” lowercase in all four guides. “Mother-in-Law” capitalizes “Law” but keeps “in” lowercase.
Capitalize the second element if it is a proper noun or proper adjective. “Anti-American” capitalizes “American” because it is a proper adjective.

A common error is capitalizing the second part of a hyphenated word simply because it follows a hyphen. The hyphen does not make a word important — apply the same test as for any word: noun, verb, adjective, adverb, or subordinating conjunction gets a capital; article, preposition, or coordinating conjunction stays lowercase.

How Case Converter Tools Apply — and Misapply — Title Case Rules

A case converter tool can save time, but it is only as good as its rule set, and most tools implement a single simplified version of title case. Here is where they typically go wrong.

Mistake 1: Capitalizing every word. The most common tool error is treating title case as “capitalize each word.” A tool that turns “The Old Man and the Sea” into “The Old Man And The Sea” is applying start case, not any style guide — if your tool capitalizes “and,” “the,” and “of” mid-title, it is wrong under all four guides.

Mistake 2: Using one guide’s rules while claiming another’s. Many tools offer AP, APA, MLA, and Chicago modes, but some simply relabel the same output. Test a tool before trusting it: convert “a journey through the night” and “what if we tried a different approach.” Correct Chicago/MLA output is “A Journey through the Night” and “What If We Tried a Different Approach”; correct AP/APA output is “A Journey Through the Night” and “What if We Tried a Different Approach.” Identical output in all four modes means the modes are cosmetic.

Mistake 3: Mishandling hyphenated words. Tools frequently capitalize both halves of every hyphenated compound (“Up-To-Date” instead of “Up-to-Date”) or lowercase the second half across the board (“Well-known” instead of “Well-Known”). Check every hyphenated word by hand.

Mistake 4: Mishandling the first and last words, colons, and proper nouns. Some tools lowercase a short word even as the first or last word (“the World We Live in”), or lowercase a subtitle’s first word (“On Writing: a Memoir of the Craft”). Others force every word into a pattern, turning “iPhone” into “Iphone” and “McDonald” into “Mcdonald.” Proper names keep their own capitalization — scan for first and last words, colons, and brand or personal names, and fix them by hand.

The practical workflow: let a converter do the mechanical bulk, then proofread against a short checklist — first word, last word, words after colons, long prepositions (AP/APA), subordinating conjunctions (MLA/Chicago), hyphenated words, and proper nouns. That two-minute check catches nearly every tool error.

Book Titles, Headlines, and YouTube Titles

Book titles

Book titles follow the publisher’s style, which in American publishing usually means Chicago headline style — hence “The Girl Who Played with Fire” (lowercase “with”), not the AP-style “With.” When citing a book, reproduce its title as published; do not re-capitalize it into your own style. The same applies to song, album, and film titles.

Newspaper and website headlines

News headlines vary more than book titles: The New York Times traditionally uses title case, while the BBC and many digital-first outlets use sentence case, and individual publications have house styles that may modify a guide. For a specific publication, its house style beats any general guide; for your own site, pick one guide and apply it consistently — readers notice inconsistency far more than they notice which guide you chose.

YouTube and social media titles

YouTube titles are a free-for-all, but the same principles apply. Title case looks polished and professional; sentence case looks casual and conversational. Either can work — the best-performing creators are usually consistent rather than strictly correct. Avoid two things: ALL CAPS titles, which read as shouting and look like clickbait, and random capitalization, where some minor words are capitalized and others are not for no reason.

On YouTube, the first words of a title matter more than the capitalization style, because titles are often truncated on small screens. Put the most informative words first, then apply your title case rules — capitalization will not save a title whose key words are buried at the end.

How to Choose a Style — and Stay Consistent

If no publication or instructor has assigned you a guide, choose by context: AP for newsrooms and journalism classes, APA for psychology, education, business, and the social sciences, MLA for literature, language, and the humanities, Chicago for books and general publishing — and for your own blog or website, pick any one guide and use it for every title. Consistency is the style.

Most title case errors come from applying a rule from the wrong guide — capitalizing “Through” in an MLA paper, or lowercasing “If” in a Chicago manuscript. Keep a one-page cheat sheet: the first-and-last-word rule, the subtitle rule, your guide’s preposition rule, and the hyphenated-word rule.

Quick Title Case Checklist

Before you publish any title, run through this list:

Is the first word capitalized, whatever it is?
Is the last word capitalized, whatever it is?
Is the first word after any colon capitalized?
Are all nouns, pronouns, verbs, adjectives, and adverbs capitalized?
Are articles (a, an, the) lowercase in the middle of the title?
Prepositions: AP/APA — are four-or-more-letter prepositions capitalized and shorter ones lowercase? MLA/Chicago — are all prepositions lowercase (except first/last/subtitle words)?
Conjunctions: are coordinating conjunctions (and, but, or, nor, for, so, yet) lowercase? Are subordinating conjunctions capitalized (MLA/Chicago) or handled by length (AP/APA)?
Is “to” lowercase in infinitives?
Are hyphenated words handled by word class, not by the hyphen?
Do proper nouns keep their own capitalization (iPhone, eBay, McDonald)?

If you can answer yes to all ten, your title is correct under your chosen guide.

Frequently Asked Questions

Is “and” capitalized in title case?

No. “And” is a coordinating conjunction, lowercase mid-title under all four guides, capitalized only as the first word, the last word, or the first word of a subtitle — “The Old Man and the Sea” is correct; “The Old Man And The Sea” is not title case under any guide.

Should “with” be capitalized in a title?

It depends on your guide. AP and APA capitalize “With” (four letters); MLA and Chicago lowercase “with” (a preposition, regardless of length). This is the most common point of disagreement between the guides — always check your guide before deciding.

Is “the” capitalized in the middle of a title?

No, unless it is part of a proper name. “The” as an article is lowercase mid-title under all four guides, capitalized at the start, at the end (rare), or after a colon. But “The Beatles” and “The New York Times” keep their capital “T” everywhere — the “The” belongs to the name.

Do you capitalize “is” in title case?

Yes. “Is” is a verb, and all four guides capitalize verbs regardless of length — as with “Be,” “Am,” “Are,” “Was,” and “Were.” Lowercasing “is” because it is short is one of the most common title case mistakes.

What is the difference between title case and sentence case?

In title case, most words are capitalized except a small set of minor words. In sentence case, only the first word and proper nouns are capitalized. Book and academic paper titles generally use title case; APA reference-list article titles and many digital news headlines use sentence case.

Final Word

Title case rules reward one habit above all: deciding your guide before you start capitalizing. The guides agree on far more than they disagree about, and the disagreements are concentrated in three word types — long prepositions, short subordinating conjunctions, and hyphenated compounds. Learn your guide’s answers for those three cases, plus the first-and-last-word and subtitle rules, and proofread converter output with the checklist above.

Image concepts (to be designed, not generated here)

Same headline in four styles graphic — One sample title (e.g., “A Journey Through the Night”) rendered four times, once per guide (AP, APA, MLA, Chicago), with the differing words (“Through” vs “through”) highlighted so readers see the split at a glance. Place after the side-by-side comparison table.
Capitalization rules cheat-sheet infographic — A compact visual summary: first/last word always capitalized, articles lowercase mid-title, AP/APA length rule vs MLA/Chicago word-class rule, hyphenated-word rule, and the “to” infinitive rule. Place after the Quick Title Case Checklist section.
Editor’s desk illustration — A flat illustration of an editor’s desk with a manuscript page, red pen markings on a title, and a style guide book, used as the article’s featured image.

Title Case Rules Explained: AP, APA, MLA and Chicago Capitalization