Title case is a capitalization style for English titles and headings. It capitalizes major words and usually lowercases articles, conjunctions, and selected prepositions, but the exact result depends on the required style guide.[1][1] The safest rule is therefore simple: identify the required guide before changing any letters.
What Rules Do Most Title Case Styles Share?
Capitalize the first and last words, plus nouns, pronouns, verbs, adjectives, and adverbs. Lowercase an interior article and apply the chosen guide’s rules to conjunctions, prepositions, infinitive _to_, and hyphenated compounds.[1][2]
The shared rules solve most words in an ordinary title. Capitalize the first word even when it is an article or preposition. Capitalize the last word under the general convention even when that word would normally be minor. Capitalize proper nouns and the major parts of speech in between. Pronouns such as _it_, _my_, and _our_ take capitals. Verbs also take capitals, including short linking verbs such as _is_ and _am_.[3][2]
Articles are normally lowercase inside a title: _a_, _an_, and _the_. Coordinating conjunctions such as _and_, _but_, _or_, _for_, _nor_, _yet_, and _so_ are also lowercase in many named styles, although the exact policies are not identical.[3] These shared principles produce titles such as:
- _A Walk Through the Old Forest_
- _What Is in the Wooden Box?_
- _My Brother and His New Bicycle_
- _The Dog That Came In_
The last example capitalizes _In_ because it is the final word. _Is_ is capitalized in the second example because it is a verb, not because it has two letters.
Do not use word length as the only test. A two-letter verb can be a major word, while a three-letter article remains minor in the middle. The word’s function matters. The governing style then settles the categories on which guides disagree.
| Word in an interior position | General treatment | Example |
|---|---|---|
| Noun | Capitalize | _A Map of the Coast_ |
| Pronoun | Capitalize | _What We Found_ |
| Verb or linking verb | Capitalize | _Why It Is Useful_ |
| Adjective or adverb | Capitalize | _A Quiet and Carefully Planned Visit_ |
| Article | Lowercase | _Across the River_ |
| Coordinating conjunction | Usually lowercase; check the guide | _Bread and Butter_ |
| Preposition | Check the guide and its length rule | _A Path through/Through History_ |
| Infinitive _to_ | Check the guide | _How to/To Begin_ |
How Do APA, MLA, AP, and Other Styles Differ?
The main differences concern prepositions, infinitive _to_, conjunction length, and hyphenated words. APA, MLA, and AP can therefore capitalize the same title differently.[1][3][2][4]
Use a named style consistently. The table below summarizes only rules supported by the cited evidence; it is not a substitute for a publisher’s current house sheet.
| Style or authority | Prepositions | Infinitive _to_ | Hyphenated terms and other distinctions |
|---|---|---|---|
| APA | Lowercase prepositions of up to three letters; capitalize words of four letters or more | Follow the style’s word rules | Capitalize major elements, but lowercase the second element after a hyphenated prefix in a compound modifier[3][2] |
| MLA, 9th edition | Lowercase prepositions regardless of length | Lowercase | Capitalize the second part of a hyphenated major word; lowercase the second word after a hyphenated prefix[1][2] |
| AP composition-title rules | Lowercase articles and prepositions or conjunctions of three letters or fewer; capitalize words of four letters or more | Capitalize | Capitalize the first, last, and principal words[4] |
| New York Times rules represented in the frozen evidence | Lowercase selected short prepositions, but capitalize other short prepositions and all longer ones | Not established by this evidence | Uses its own word list rather than one simple length cutoff[3] |
Consider _A Journey over New Ground_. MLA lowercases _over_ because MLA lowercases prepositions regardless of length. APA and AP capitalize _Over_ because their cited cutoff lowercases prepositions only through three letters.[3][4] Neither rendering is universally correct; the guide determines the answer.
The same caution applies to _to_. MLA uses _How to Begin Again_, while the cited AP rules use _How To Begin Again_.[1][4] Do not “correct” one form without knowing the guide.
Hyphenation needs two decisions: identify the elements’ grammatical roles, then apply the guide. Under the cited MLA rules, a hyphenated major word can capitalize both major elements, as in _Self-Report_. A compound modifier formed with a prefix can instead lowercase its second element, as in _Anti-hero_.[1] Under the cited APA summary, the second element after a hyphenated prefix is likewise lowercase.[2] Avoid treating every hyphen as a command to capitalize the next letter.
Scientific names form a separate case. Preserve a scientific name’s established capitalization rather than forcing an ordinary title-case pattern onto it. For example, a title containing _Homo sapiens_ keeps the genus capitalized and the species name lowercase; the ordinary major-word rule does not change that established form.
How Can You Apply and Check Title Case?
Mark the fixed capitals first, classify each remaining word, apply one named guide to disputed words, and proofread the finished title without switching conventions halfway through.
Use this sequence:
- Write down the required style: APA, MLA, AP, a named house style, or another explicit standard.
- Capitalize the first and last words.
- Capitalize proper nouns, nouns, pronouns, verbs, adjectives, and adverbs.
- Lowercase interior articles.
- Check every conjunction and preposition against the selected guide.
- Check infinitive _to_ and each hyphenated term separately.
- Preserve established forms for abbreviations, brand names, and scientific names instead of guessing from letter count.
- Read the result once for consistency.
During the final read, compare repeated words as well as individual letters. If _through_ appears twice in equivalent positions, it should receive the same treatment both times. Mark every change that depends on the chosen guide, especially a long preposition, infinitive _to_, or hyphenated expression. This creates a short audit trail: another editor can see which rule produced the capital without reconstructing the whole decision. When the required guide is unknown, flag the disputed word instead of presenting one guide’s rendering as the only correct answer.
Here is a worked example using the cited MLA rules:
Original: _a practical guide to walking through a city_
- _A_ is first, so capitalize it.
- _Practical_, _Guide_, _Walking_, and _City_ are major words.
- _to_ is an infinitive particle, which MLA lowercases.
- _through_ is a preposition, and MLA lowercases prepositions regardless of length.
- _a_ is an interior article.
Result: _A Practical Guide to Walking through a City_.[1][2]
Now apply the cited AP rules to the same words. _Through_ has more than three letters, so AP capitalizes it. In this title, _to_ introduces the gerund phrase _walking through a city_, so it functions as a short preposition and remains lowercase. The result is _A Practical Guide to Walking Through a City_.[4]
Practice with the named style shown in parentheses:
- _what we know about the moon_ (MLA)
- _a road over the mountain_ (APA)
- _how to plan a trip_ (AP)
- _self-report methods for new students_ (MLA)
Answer key:
- _What We Know about the Moon_ — _We_ and _Know_ are major words; MLA lowercases the preposition _about_.
- _A Road Over the Mountain_ — the cited APA rule capitalizes the four-letter preposition _Over_ and lowercases the article _the_.
- _How To Plan a Trip_ — the cited AP rule capitalizes infinitive _To_ and lowercases the interior article _a_.
- _Self-Report Methods for New Students_ — the cited MLA rule capitalizes both major elements of _Self-Report_ and lowercases the preposition _for_.[1][2]