Case Converter

UPPER, lower, aLtErNaTiNg and iNVERSE change letters only and leave everything else in place, using the Unicode default case mappings (so ß becomes SS and accented letters keep their accents). Sentence case lower-cases the text and capitalises the first letter after a full stop, question or exclamation mark, or a line break.

camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and dot.case first split the text into words: at spaces and punctuation, at a lower-case-to-upper-case boundary (fooBar → foo Bar) and at the end of an acronym (HTTPServer → HTTP Server). Digits stay with the word they touch (utf8 stays utf8). The words are then lower-cased and joined, which is why the round trip camel → snake → camel is exact.

Every word is capitalised except a fixed list of small words (a, an, the, and, but, or, nor, for, so, yet, at, by, in, of, on, to, up, as, if, vs), which stay lower unless they begin or end the line; hyphenated parts are capitalised too. Style guides differ — AP capitalises words of four letters or more, Chicago lower-cases prepositions of any length — so this is one explicit rule, not a claim to match any of them.

Locale-specific casing (Turkish dotted İ and dotless ı, Greek final sigma, German ß in names) follows the Unicode default, which may not be what a given language expects. Proper nouns and acronyms inside title case are not recognised. Text up to 1 MB is converted on your machine; nothing is uploaded. The same four anonymous usage counts as the rest of the site apply.