BRev Title Case converter
Title Case capitalises the significant words in a heading and leaves the minor ones lowercase — and the whole difficulty is that “minor” is defined differently by every style guide. This is the one style on the site that is an editorial decision rather than a technical one, which is why the converter offers AP, APA, Chicago, NYT, Wikipedia and British rather than a single answer.
The differences are narrower than the arguments about them suggest, and they land on specific words rather than whole sentences. Take “the cat is out of the XML bag”: AP, APA and NYT all give “The Cat Is out of the XML Bag”, lowercasing “out” because they read it as a preposition — while Chicago and British capitalise it, reading it as an adverb in that phrase. Every one of them capitalises the first and last word, capitalises “Is” despite its length, and lowercases “the” and “of”. Run the seeded converter below and compare the six outputs on your own headline; on many headlines four of them agree exactly.
A separate question is whether to use Title Case at all. Most current design systems — Google’s Material and GOV.UK among them — prefer sentence case for interface text, on the grounds that it is easier to read, easier to localise, and removes an entire class of arguments about which words to capitalise. Title Case remains standard for article headlines, book and film titles, and formal document sections.
Title Case — worked through
Every line below is produced by the same converter that runs on this page, so the example and the tool cannot disagree.
| Input | Title Case | Note |
|---|---|---|
| parse xml file | Parse XML File | The canonical shape of this style. |
| the cat is out of the XML bag | The Cat Is out of the XML Bag | AP style, the converter’s default. |
| the cat is out of the XML bag | The Cat Is Out of the XML Bag | Chicago instead of AP — it capitalises words AP reads as prepositions. |
Where Title Case is the convention
| Ecosystem | What it applies to |
|---|---|
AP style | Journalism, press releases, most marketing copy. Lowercases articles, short conjunctions and prepositions of three letters or fewer; four letters and up are capitalised. |
Chicago | Books, academic and long-form publishing. Same family of rules as AP, but it parts company on words that can be read as either preposition or adverb — “Out”, “Up”, “On” — which Chicago capitalises where AP does not. |
APA | Academic papers and references. Lowercases minor words of three letters or fewer; used alongside sentence case for its own reference-list titles. |
Sentence case | Product UI, documentation and anything localised. Only the first word and proper nouns are capitalised — fewer decisions, better readability, far easier to translate. |
The acronym trap
Acronyms must not be lowercased by the small-word rules — an “API” is not the word “a”, and “XML” must never become “Xml” because a naive title-caser applied a capitalise-first-letter rule to it. The converter keeps a list of known acronyms and preserves them exactly, which is what stops “Parse the XML File From the ERP API” degrading into “Parse The Xml File From The Erp Api”. Add your own product names and initialisms to that list before running a batch of headings.
مرحبا بالعالم. The Unicode slug keeps the original script.FAQ
Which words are not capitalised in Title Case?
Depends on the guide. AP and APA lowercase minor words of three letters or fewer; Chicago lowercases prepositions of any length plus articles and coordinating conjunctions. Every guide capitalises the first and last word regardless.
Should I use Title Case or sentence case for buttons and headings?
Sentence case for product interfaces — Material Design and GOV.UK both recommend it, and it localises far more cleanly, since capitalisation rules differ by language. Title Case suits editorial headlines and formal titles.
Why do the style guides disagree?
They were written for different media with different traditions — newswire brevity, academic citation, book publishing. There is no underlying rule to be right about, so the only real error is switching between them within one publication.