How to use this case converter
- Paste or type into the Your text box. It is remembered in your browser, so a reload does not lose it.
- Press one of the case buttons. The result appears in the result box, and the button stays highlighted so you know which rule produced it.
- Copy the result, or feed it back in with "Use result as input" to apply a second conversion.
Title Case rules
Title Case uses one fixed English rule set, rather than a selectable AP or Chicago style: capitalize every word except short function words, which stay lowercase in the middle of a title. The lowercase list is a, an, and, as, at, but, by, for, if, in, nor, of, on, or, per, so, the, to, up, vs, via, yet. Three exceptions override the list: the first word of a line, the last word of a line, and the first word after a colon, full stop, question mark or exclamation mark are always capitalized. Hyphenated words capitalize both halves, so self-service becomes Self-Service. Words that are already in capitals, such as NASA, are lowercased first; if you need them kept, fix those by hand.
Sentence case
Everything is lowercased, then the first letter of each sentence is capitalized, where a sentence starts at the beginning of a line or after a full stop, question mark or exclamation mark followed by a space. The word I is capitalized too. Proper nouns are not recognized; the tool has no dictionary of names, on purpose, because guessing wrong is worse than leaving it to you.
camelCase, snake_case and kebab-case
These split the input into words first, on spaces, punctuation and existing case boundaries, so user ID number, user_id_number and UserIDNumber all yield the same list of words. Then camelCase lowercases the first word and capitalizes the rest with no separators (userIdNumber), snake_case joins lowercase words with underscores (user_id_number), and kebab-case uses hyphens (user-id-number), which is what URLs, CSS class names and most CLI flags expect. Line breaks are treated as separators, so convert one identifier at a time if you want them kept apart.
Case converter FAQs
Which words stay lowercase in Title Case?
Articles (a, an, the), short conjunctions (and, but, or, nor, so, yet) and short prepositions (as, at, by, for, in, of, on, per, to, up, via, vs), unless the word is first or last in the line or follows a colon, full stop, question mark or exclamation mark. Everything else is capitalized.
Does Sentence case keep names and acronyms capitalized?
No. Sentence case lowercases everything, then capitalizes the first letter of each sentence and the pronoun I. It cannot tell that NASA or London are proper nouns, so check those by eye after converting.
How does camelCase split my text into words?
On spaces, punctuation and existing case boundaries. So "user ID number", "user_id_number" and "UserIDNumber" all become userIdNumber. Digits stay attached to the word they follow.
Does it work with accented letters and other alphabets?
Yes. Conversions use the browser's Unicode-aware case rules, so é, ß, Ω and Cyrillic letters change case correctly. The small-word list for Title Case is English only.
Can I chain conversions?
Press "Use result as input" to move the output into the input box, then pick another case. It is handy for lowercasing first and then applying Title Case to shouting text.
Is my text sent anywhere?
No. The conversion is a few lines of JavaScript running in your browser. The input is kept in localStorage so it survives a reload, and nothing else is stored. See the privacy page.