Text Case Converter

How to use it

1. 1Paste your text into the box marked "Your text"Paste the text you want converted. Everything happens inside your browser — nothing is uploaded, so there is nothing for us to store, log or lose.
2. 2Read the result as it updatesThere is no button to press. Choose a case style and the converted text appears immediately. The output recomputes every time you change the text or one of the options above it.
3. 3Pick the style you actually needUPPER, lower, Title Case, Sentence case, camelCase, PascalCase, snake_case and kebab-case are all offered. The last four are for code; the first four are for prose.
4. 4Check Title Case against your style guideWhich small words stay lowercase is a matter of house style, not of fact, and no two guides agree. Read the output rather than assuming it matches yours.
5. 5Convert back if you got the wrong oneNothing is destroyed — your original stays in the input box, so switching styles costs nothing.
6. 6Copy or download the resultThe buttons under the output put it on your clipboard or save it as a file, and each one says exactly what it will copy or download. Any note about something the tool changed or deliberately left alone is shown with the result rather than hidden.

About this tool

Converts text between upper case, lower case, title case, sentence case and the programmer conventions — camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE.

The programmer cases need more than changing letters: turning parseHTTPResponse into parse_http_response requires seeing that HTTPResponse is two words. Splitting on capitals alone gets that wrong, and the boundary rules live in one place so every conversion agrees.

Understanding the result

Case conversion is locale-aware. In Turkish a dotless "ı" upper-cases to "I" and a dotted "i" to "İ"; German "ß" upper-cases to "SS" and gets longer. Using the locale-insensitive functions would change the word.

Title case keeps the short words — a, an, the, of, to — lower case unless they are first or last, following the common English style guides.

Sentence case capitalises the first letter of each sentence and leaves the rest alone, so acronyms and proper nouns already in the text survive.

Example

parseHTTPResponse

snake_case:    parse_http_response
kebab-case:    parse-http-response
CONSTANT_CASE: PARSE_HTTP_RESPONSE

Limitations

• Title case cannot know your house style. The list of words kept lower case is deliberately short, because a long one starts making choices you did not ask for.
• Sentence case does not know which words are proper nouns, so it will not capitalise a name that was typed in lower case.
• Converting to camelCase or snake_case discards the original separators. The conversion is not reversible in general.
• Some scripts have no concept of case at all. Tamil, Chinese, Arabic and Hebrew text passes through unchanged, which is correct.

Questions