Title case can feel a bit arbitrary because there isn't just one universal rule—it depends on the style guide you are following (like APA, MLA, Chicago, or AP). However, across almost all styles, there is a core logic to what gets capitalized and what stays lowercase.
Here is a practical guide to mastering title capitalization for books, chapters, and headings.
1. The Universal Golden Rules
No matter which style guide you use, these three rules never change:
- Always capitalize the first and last word of a title or heading, regardless of what part of speech they are (e.g., How to Wake Up).
- Always capitalize major parts of speech: Nouns, pronouns, verbs, adjectives, and adverbs.
- Always capitalize verbs that look small: Short verbs like Is, Are, Was, Be, and Go must always be capitalized because they are verbs.
2. What to Keep Lowercase
As a general rule, you keep short grammatical "helper" words lowercase—unless they are the first or last word of the title.
Articles
Always lowercase: a, an, the.
Coordinating Conjunctions
Always lowercase: and, but, for, or, nor (and usually so and yet depending on the guide).
Prepositions
This is where style guides differ most. Prepositions are words that show relationship or direction (like in, on, with, to, by, from).
- Chicago, MLA, and APA Styles: Lowercase all prepositions, no matter how long they are (through, between, against, with).
- AP Style (Journalism): Capitalize any preposition that is 4 letters or longer (With, Into, Through). Lowercase only the tiny ones (in, on, by, to).
Watch out for To: Keep to lowercase whether it is a preposition (Journey to the Center of the Earth) or part of an infinitive verb (How to Write a Book).
3. Special Scenarios
Hyphenated Words
If your title includes a hyphenated word (like Self-reliance or Run-in), capitalization depends on your style guide, but the safest, most common modern approach is to capitalize both parts if they are major parts of speech (e.g., The Creative Self-Expression Workbook).
Subtitles
Always treat a subtitle as a brand-new title. Capitalize the first word following the colon, even if it is a small word like a or the.
- Example: Children's Books: A Complete Guide to Success
Quick Reference Comparison
| Example Title | Style Rule Used | Why? |
|---|---|---|
| The Lion, the Witch and the Wardrobe | Chicago / MLA | "the" and "and" are lowercase inside the title. |
| Walking Through the Woods | Chicago / MLA | "Through" is lowercase because it's a preposition. |
| Walking Through the Woods | AP Style | "Through" is capitalized because it is $\ge$ 4 letters. |
| What We Are Waiting For | Universal | "Are" is a verb and "For" is the last word; both must be capitalized. |
4. Headings vs. Book Titles
When formatting documents or chapters, you have two structural choices for your headings:
-
Title Case (Like a Book): Every major word is capitalized. Use this for book titles, chapter titles, and main headings (H1).
-
Example: Guidelines for Child Safety in Fiction
-
Sentence Case: Capitalize only the first word and any proper nouns, exactly like a normal sentence. This is increasingly popular for subheadings (H2, H3) in modern layouts because it feels cleaner and is easier to read quickly.
-
Example: Guidelines for child safety in fiction
The most important rule of all is consistency. Pick one style (like lowercase prepositions) and stick to it throughout your entire manuscript.