Title Case vs Sentence Case – Which One to Use

Title case puts a capital letter on every important word: How to Fix a Leaking Tap in Ten Minutes. Sentence case capitalizes only the first word and any names: How to fix a leaking tap in ten minutes. Both are correct. They just belong in different places, and mixing them on one page is what makes writing look careless.

What title case is

In title case, the first word, the last word and every "major" word start with a capital. The small words stay small: articles (a, an, the), short prepositions (of, in, to, on) and coordinating conjunctions (and, but, or, for, nor).

Which words count as "small" is where the style guides part company. APA keeps any word of four letters or more capitalized, so With and From get capitals. Chicago and MLA keep every preposition lowercase no matter how long it is, so the same title has with and from. That is not a mistake in either guide. It is a different rule, and you follow whichever one your publisher, teacher or house style asks for. The title capitalization tool on this site applies nine of those rule sets, so you can see the difference on your own title in a second.

What sentence case is

Sentence case is exactly what it sounds like: the heading is capitalized as if it were a sentence. The first word gets a capital. Proper nouns get a capital. Everything else is lowercase.

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Notice that iPhone and Chicago Manual of Style keep their capitals in sentence case. Sentence case is not the same as lowercase. Names are still names.

Where title case belongs

Title case is for things that have a title in the formal sense: a book, a film, a report, an article, a chapter, a webinar, a podcast episode. It is also the usual choice for headlines in print newspapers and most American magazines, for the names of products and features, and for the top-level title of an academic paper.

A quick test: would this appear in italics or quotation marks if you mentioned it in a sentence? If yes, it is a title, and title case is the safe choice.

Where sentence case belongs

Sentence case has taken over most of the web, and for a practical reason. It is easier to read on screens, and it looks less like an advertisement. Use it for:

• Headings inside a page or document. APA 7 uses title case for its heading levels, but most web style guides (Google, Microsoft, the UK government's GOV.UK) use sentence case for every heading below the page title.
• Email subject lines. A subject in title case reads as marketing. A subject in sentence case reads as a person. Open rates follow the second one.
• Buttons, labels and menu items. Save changes, not Save Changes. Almost every current interface guideline agrees on this.
• Chart titles, table captions and figure labels in most scientific journals.

What the main style guides say

APA 7 uses both. The title of a paper and all five heading levels are in title case. Inside the reference list, the titles of articles, books and reports are in sentence case, while the names of journals stay in title case. This is the single most common source of confusion in student papers.

Chicago prefers title case ("headline style") for titles of works and allows sentence case where a publisher's house style asks for it. Its lowercase rule for prepositions is stricter than APA's.

AP uses title case for the titles of books, films and songs mentioned in copy. Headlines in most AP-style newsrooms are sentence case, which surprises people who assume news headlines are always title case.

MLA uses title case for every title in the text and in the works-cited list, with every preposition lowercase.

The mistakes that give you away

Capitalizing every word. How To Fix A Leaking Tap In Ten Minutes is not title case in any guide. The small words have to stay small.

Forgetting the last word. Every guide capitalizes the final word even if it is short. What the Rule Is For, not What the Rule Is for.

Mixing cases on one page. One heading in title case and the next in sentence case tells the reader that nobody checked. Pick one for the headings and keep it; the page title can still be in title case.

Treating "Is" as a small word. It is a verb. Every guide capitalizes it. The length rule in APA and AP applies to prepositions and conjunctions, not to verbs.

The one rule that settles it

If the thing you are capitalizing is the name of a work, use title case. If it is a heading, a label or a line of interface text, use sentence case unless your style guide says otherwise. When the style guide does say otherwise, follow the style guide, because the person reading your work is checking against it, not against this article.

And when the title is already written and you just need the capitals fixed, paste it into the converter, pick the style, and copy the result. It handles hyphens, colons and short verbs the way each guide expects, which is exactly the part that is tedious to do by hand.