What each case is for
| Case | Example | Used for |
|---|---|---|
| Sentence case | The lord of the rings | Body text, most modern headings, UI labels |
| Title Case | The Lord of the Rings | Book and article titles, headlines in US style |
| UPPERCASE | THE LORD OF THE RINGS | Short labels and acronyms — hard to read in bulk |
| lowercase | the lord of the rings | Normalising data, tags, email addresses |
| camelCase | theLordOfTheRings | Variables in JavaScript, Java, Swift |
| PascalCase | TheLordOfTheRings | Class names, React components, C# types |
| snake_case | the_lord_of_the_rings | Python, Ruby, SQL columns |
| kebab-case | the-lord-of-the-rings | URLs, CSS classes, file names |
| CONSTANT_CASE | THE_LORD_OF_THE_RINGS | Constants, environment variables |
The buttons are grouped the way the cases are used: Prose for anything a reader reads, Code for identifiers. Your text stays in the left pane whichever you pick, so trying one case never costs you the original — the old version of this tool converted in place, which meant a single click on lowercase threw away capitalisation you could not get back.
How title case is applied here
Title case is not simply “capitalise every word” — that is a separate button here, Each Word, because the two produce different results and people want both. Title case capitalises the first and last words and everything in between except short articles, conjunctions and prepositions: a, an, and, as, at, but, by, for, in, nor, of, on, or, per, so, the, to, up, via, vs, along with the longer prepositions about, after, before, between, during, from, into, onto, over, through, under, upon, with, within, without.
So the lord of the rings becomes The Lord of the Rings, not The Lord Of The Rings. Three details most converters miss are handled here:
- Acronyms survive. an interview with NASA becomes An Interview with NASA, not Nasa. That is the Keep ALL-CAPS words option, on by default; turn it off if your source is shouting and you want it calmed down.
- Hyphenated compounds capitalise both parts, but not a small word in the middle: Mother-in-Law.
- A subtitle after a colon starts afresh, so The Lord of the Rings: The Fellowship of the Ring keeps its capital after the colon.
Style guides differ on prepositions of four or more letters — some capitalise Between and Through — so check the result against your house style.
Notes on the programming cases
The identifier cases discard punctuation and split on any non-alphanumeric character. That is deliberate: a stray apostrophe or comma would make the result invalid.
They also split on case boundaries in what you paste, so XMLHttpRequest becomes xml-http-request rather than one long blob, and they work line by line — paste a column of names and you get a column of identifiers back, not a single run-on one.
Common questions
Do I lose my original text?
Never. Your text stays in the left pane and the result is derived beside it, so switching between cases always works from what you pasted rather than from the last conversion. Use as text moves the result across on purpose, when you actually want to convert a conversion.
Is my text uploaded?
No. Every conversion happens in your browser on this page.
Does it handle accented characters?
Yes. Case changes use full Unicode rules, so é becomes É correctly, and accents survive the identifier cases as best they can.
