Title Case Rules: AP vs APA vs Chicago vs MLA
Updated October 22, 2026
Title case means capitalising the important words in a title and keeping the small ones lowercase. The catch is that AP, APA, Chicago and MLA each define "small" differently.
The four styles side by side
| Rule | AP | APA | Chicago | MLA |
|---|---|---|---|---|
| First and last word | Capitalise | Capitalise | Capitalise | Capitalise |
| Short words: a, an, the | Lowercase | Lowercase | Lowercase | Lowercase |
| Short conjunctions: and, but, or | Lowercase | Lowercase | Lowercase | Lowercase |
| Prepositions of 3 letters or fewer: in, on, of | Lowercase | Lowercase | Lowercase | Lowercase |
| Prepositions of 4 letters or more: over, with, from | Capitalise | Capitalise | Lowercase | Lowercase |
| Word after a colon | Capitalise | Capitalise | Capitalise | Capitalise |
The same title in each style
Take "the quick brown fox jumps over the lazy dog". The only difference is the word over, a preposition of four letters:
| Style | Result |
|---|---|
| AP | The Quick Brown Fox Jumps Over the Lazy Dog |
| APA | The Quick Brown Fox Jumps Over the Lazy Dog |
| Chicago | The Quick Brown Fox Jumps over the Lazy Dog |
| MLA | The Quick Brown Fox Jumps over the Lazy Dog |
Which style should you use?
- AP: journalism, news websites and most business writing in North America.
- APA: psychology, education and the social sciences (headings and reference titles).
- Chicago: books, history and many publishers.
- MLA: literature and the humanities.
- Not told which? Follow the style guide of the publication or your teacher, and be consistent within one document.
Common mistakes
- Lowercasing the first or last word. Both are always capitalised, even if they are small words such as "A" or "Up".
- Capitalising every word. That is Capitalized Case, not title case.
- Forgetting hyphenated words: capitalise the important parts, as in "Self-Driving Cars".
- Changing the capitals in brand names such as iPhone or eBay.
Convert a title in one click
The Title Case tool follows headline rules, and the AP, APA and Chicago / MLA pages apply each style exactly. Paste your title, copy the result, and check names and brand words by eye.
Frequently asked questions
Is "is" capitalised in a title?
Yes. Verbs such as is, are and be are always capitalised in all four styles, even though they are short.
What is the difference between title case and sentence case?
Title case capitalises the main words of a title. Sentence case capitalises only the first word and proper nouns, as in a normal sentence. Many modern websites and style guides prefer sentence case for headings.