Title Case Rules: Which Words to Capitalize in a Headline

In title case you capitalize the first word, the last word and every important word: nouns, pronouns, verbs, adjectives, adverbs and most conjunctions that introduce a clause. You lowercase the small connecting words in between: the articles a, an and the, the conjunctions and, but, or, nor, for, so and yet, and short prepositions such as of, in and on. The only real argument between style guides is where a preposition becomes long enough to earn a capital.

This guide goes through the rules one word type at a time, with example headlines for each, and ends with a table that shows the same seven headlines in four house styles. If you just need a heading fixed, paste it into the case converter and press Title Case.

The five rules most styles share

1. Capitalize the first word of the title and of any subtitle, whatever it is: The Year We Moved, A Short History of Glass.
2. Capitalize the last word, even a tiny one: Something Worth Fighting For, Where the Road Leads To.
3. Capitalize nouns, pronouns, verbs, adjectives and adverbs, however short: Why It Is So Hard to Say No.
4. Lowercase articles and coordinating conjunctions in the middle: Bread and Butter for a Cold Night.
5. Lowercase the word to, whether it starts an infinitive or works as a preposition: How to Get to the Coast.

Almost every disagreement you will see in published titles comes from prepositions, from words that can be two parts of speech, or from hyphenated compounds. Those are covered below.

Short words that are still capitalized

The most common title case mistake is lowercasing a word because it is short. Length is not the test; the job the word does in the sentence is. These are all capitalized in every major style:

• Short verbs: Is, Are, Was, Be, Do, Go and Has. Honesty Is a Habit, not Honesty is a Habit.
• Pronouns: It, He, She, We, Me, Us, His and Its. Why We Keep Coming Back; A Town and Its Bridges.
• Short adverbs: Not, Too, How and Now. Not Now, Not Ever; When Enough Is Too Much.
• The word No: No Place Like Home.
• Short nouns and adjectives: Big Dogs and Old Men; The Day the Sun Set Early.

A quick check is to ask whether the word carries meaning on its own. If you can underline it and say what it refers to or what it does, it gets a capital.

Conjunctions: two kinds, two treatments

Coordinating conjunctions join equal parts, and there are only seven: for, and, nor, but, or, yet and so. They are lowercase in the middle of a title in all the big styles: Slow and Steady, Cheap but Cheerful, Now or Never.

Two of the seven double as other parts of speech, which changes the answer. So is a conjunction in Rain Came, so We Stayed In but an adverb, and capitalized, in Why Is Everything So Expensive. For is a conjunction only in literary phrasing; in most titles it is a preposition, as in Recipes for Busy Weeknights, and lowercase either way.

Subordinating conjunctions introduce a clause: if, because, when, while, although, since, until, that and than. Chicago and MLA capitalize them, as in What Happens When the Power Goes Out and Stay Home If You Feel Ill. Styles that judge minor words by length, such as AP, lowercase the ones under four letters, so If becomes if there. The word as is a special case: Chicago lowercases it in every role, so Life as a Night Nurse keeps a small as.

Prepositions: where the styles split

Prepositions show position or relation: of, in, on, at, by, with, from, about, between. Everyone agrees that the short ones stay lowercase in the middle of a title. The styles part ways on the longer ones.

Chicago's cut-off at five letters is new in its 18th edition, published in 2024. From the 12th edition, published in 1969, through the 17th, Chicago said to lowercase prepositions regardless of length, which is why many older books and house styles print Walking through the Forest with a small through. If your organization follows an older Chicago-based style sheet, check which edition it was written against.

Multi-word prepositions follow the same idea word by word. MLA lowercases according to and other than wherever they fall; a length-based style would give The Garden According to Grandma.

Particles and adverbs that look like prepositions

Up, down, in, off, out and over are often not prepositions at all but part of a phrasal verb, where they change the meaning of the verb. In that role they are adverbs and get a capital in every style:

• How to Set Up a Home Office: set up means install, so Up is capitalized.
• Log In to Your Account: In belongs to the verb log in and is capitalized, while to is a true preposition and stays lowercase.
• Turn Off Autoplay on Every Device: Off completes the verb; on introduces a place and is lowercase.
• Climbing up the Stairs: here up has an object, the stairs, so it is a preposition and lowercase.

The test is whether the word has an object after it. Up the stairs has one; set up a desk moves the object onto the verb. Because automated tools cannot reliably make this call, a converter that lowercases up everywhere will get phrasal verbs wrong, and one that capitalizes it everywhere will get the stairs wrong. Read these titles once more by eye.

Colons, dashes and hyphenated words

After a colon, the first word of a subtitle is capitalized, even an article: Night Trains: A Traveller's Handbook. The same holds when a question mark splits a title in two: Why Sleep? The Case for Resting.

Hyphenated compounds are treated part by part. Current Chicago and APA agree; older Chicago editions did not:

• Both capitalize ordinary compounds in full: Self-Driving Cars, Long-Term Planning, Twenty-First Century Homes.
• Both leave articles, prepositions and short conjunctions lowercase inside a compound: A Mother-in-Law's Advice, Up-to-Date Maps.
• After a prefix that cannot stand as a word on its own, both now capitalize the second part too: Anti-Intellectual Pursuits, Anti-Inflammatory Diets, Pre-Election Polls. APA has long capitalized both parts of a hyphenated major word, and Chicago adopted the same treatment in its 18th edition.
• The 17th and earlier editions of Chicago kept the part after such a prefix lowercase, giving Anti-inflammatory Diets and Pre-election Polls, so you will still see that form in books and style sheets written before 2024.

The same headlines in four styles

Each row starts from a lowercase draft. Differences between the columns are all caused by the rules above: preposition length, the treatment of short subordinating conjunctions, and nothing else.

The second row shows the only place where a short conjunction matters: if is lowercased by length in AP and APA but capitalized as a subordinating conjunction by Chicago and MLA. The last three rows come out the same everywhere, which is typical: most everyday headlines contain no long prepositions and no conflict at all.

Words that ignore the rules

• Proper nouns and acronyms keep their own spelling in any position: Why the UN Meets in New York, Saving Money on LED Bulbs.
• Names with inner capitals are written as their owners write them: The McKenzie Family Archive.
• Numbers stay as figures when you would write them that way in running text, and the word after a figure is treated normally: 10 Ways to Sleep Better, The 3 Rules of Bread.
• Deliberately lowercase words, such as a product or project name that its creator writes without capitals, can stay lowercase in the middle of a title; many editors rephrase to avoid starting a title with one.
• Versus abbreviated as vs. is lowercase: Cats vs. Dogs in Small Flats.

Title case or sentence case?

Title case signals a name: of a book, a film, a report, a chapter. Sentence case, where only the first word and proper nouns get capitals, reads like normal prose and is harder to get wrong. Many news sites, many software interfaces and a growing number of blogs now use sentence case for headlines, and academic reference lists in several styles give article titles in sentence case while keeping journal names in title case.

Whichever you choose, pick one for each level of heading and keep it across the whole document or site. Mixed styles on the same page look like mistakes even when each heading is correct on its own terms.