Case Converter
Paste some text, pick a case, and copy the result. It handles everyday writing (Title Case, Sentence case) as well as programmer formats like camelCase, snake_case and kebab-case.
Your text is converted inside your browser and is never sent to our server.
How to use the Case Converter
- Paste your text into the top box. It can be a headline, a paragraph, or a list of names with one per line.
- Click the case you want. The result appears below and keeps updating if you edit the input.
- For Title Case, decide whether short words such as "of", "and" and "the" should stay lowercase, and whether acronyms like "NASA" or "PDF" should be left alone.
- Press Copy result, or Use result as input if you want to chain another conversion.
What each option does
- UPPERCASE / lowercase change every letter, including accented ones such as é or ő, using your browser's built-in Unicode rules.
- Title Case capitalizes the first letter of each word. With the first option on, a fixed list of short words (articles, coordinating conjunctions and short prepositions such as a, an, the, and, but, or, of, in, on, to, with) stays lowercase unless it is the first or last word or follows a colon or a sentence end. This is a simple, predictable rule, not a full implementation of AP, Chicago or APA style; those guides disagree with each other on details such as longer prepositions ("between", "about"), so check your style guide for anything important.
- Sentence case lowercases everything, then capitalizes the first letter of the text, the first letter after a period, question mark or exclamation mark, the first letter of each line, and the pronoun "I".
- camelCase, PascalCase, snake_case, CONSTANT_CASE, kebab-case split the text into words, drop punctuation and join the words in the chosen style. Existing boundaries are recognized, so
userIDValue,user_id_valueandUser ID valueall becomeuserIdValuein camelCase. Each line is converted separately, which is handy for a list of field names.
Limitations worth knowing
A converter cannot tell a proper noun from an ordinary word. Sentence case will turn "Paris" into "paris" unless it starts a sentence, and Title Case will capitalize "iPhone" as "Iphone" unless that word is already in ALL CAPS and you have the acronym option on. Read the result before you publish it. Abbreviations such as "e.g." also count as a sentence end in Sentence case, so the next word gets a capital letter.
The programmer formats remove apostrophes and other punctuation and lowercase acronyms ("HTML parser" becomes htmlParser). Some codebases prefer HTMLParser; adjust by hand if yours does.
Frequently asked questions
Which Title Case style does this follow?
None exactly. It uses one simple rule: capitalize every word except a short list of articles, conjunctions and short prepositions, which stay lowercase in the middle of a title. AP, Chicago, APA and MLA each have their own exceptions, so treat the output as a starting point for formal publishing.
Will it keep acronyms like NASA or HTML?
In Title Case and Sentence case, yes, if Keep words already in ALL CAPS is ticked. A word counts as an acronym when it has at least two letters and is entirely uppercase. In the programmer formats acronyms are lowercased so the output is consistent.
Does it work with accented letters and other alphabets?
Yes. It uses Unicode-aware matching, so letters such as ä, ñ, ő, Greek or Cyrillic are converted correctly. Scripts without upper and lower case, such as Chinese or Arabic, pass through unchanged.
Can I convert a list of variable names at once?
Yes. Put one name per line. The camelCase, PascalCase, snake_case, CONSTANT_CASE and kebab-case options convert each line on its own and keep the line breaks.
Is my text stored anywhere?
No. The conversion is plain JavaScript running in this tab. Nothing is uploaded or saved, and the text is gone when you close the page.