Text Case Converter
Change text between uppercase, lowercase, simple title case, and sentence case with Unicode-aware casing.
Line breaks and punctuation are preserved. Case mapping can change the number of Unicode code points.
Converted Output
Converted text will appear here.
What each conversion actually changes
- UPPERCASE and lowercase
- These use JavaScript's default Unicode case mappings on the underlying string. They are mechanical transformations, not CSS styling, and a mapping can change the number of code points.
- Simple Title Case
- Each whitespace-separated token is lowercased and then its first letter is uppercased. It does not implement AP, Chicago, MLA, or another publication style, and it does not preserve acronyms automatically.
- Sentence case
- The text is lowercased first, then the next letter is capitalized at the start, after a line break, or after
.,!, or?. Abbreviations and quoted punctuation can make those guessed boundaries wrong.
Case mapping rewrites text, and language can affect the result
A CSS rule such as text-transform changes how text is displayed; these buttons create a new string that will be copied and stored as the converted value. Unicode mappings are not always one code point in and one code point out. German ß, for example, can expand when uppercased, so character counts, byte lengths, fixed-width fields, and database limits should be checked after conversion rather than assumed to stay constant.
The uppercase and lowercase buttons are locale-insensitive. Natural-language casing can differ by locale; Turkish dotted and dotless I are the familiar example. JavaScript exposes locale-sensitive methods separately, but this page does not ask which locale you are writing for. Names, acronyms, product spelling, scientific notation, code, and editorial title style therefore still need human judgement.
References: ECMAScript string case conversion and Unicode case-mapping guidance.
Do not use display-case conversion to normalize identifiers
Lowercasing visible text is not the same as Unicode case folding, canonical normalization, locale-aware comparison, or an application's username policy. Login names, security-sensitive identifiers, file names, database keys, and duplicate detection need comparison rules designed for that system. A copied lowercase result can look consistent while still being the wrong normalization strategy.