Case Converter
Free case converter. Change text to uppercase, lowercase, title case, sentence case, camelCase, snake_case or kebab-case instantly.
Result
Converted text appears here…
Retyping text to change its capitalisation is a waste of time, and doing it by hand in code is how inconsistent variable names get into a codebase. This converter switches between eight case styles instantly.
Paste your text, pick a style, copy the result. Everything stays in your browser.
How to use the Case Converter
Paste your text
Any length, from a single word to a whole document.
Choose a case style
Every style is converted at once, so you can see them side by side and pick the right one.
Copy the result
One click copies the version you need.
The eight styles
| Style | Example | Used for |
|---|---|---|
| UPPERCASE | HELLO WORLD | Emphasis, constants, headings |
| lowercase | hello world | Normalising input, URLs, email addresses |
| Title Case | Hello World | Headlines, book and article titles |
| Sentence case | Hello world | Body text, UI labels, buttons |
| camelCase | helloWorld | JavaScript and Java variables |
| PascalCase | HelloWorld | Class names, React components, C# methods |
| snake_case | hello_world | Python, Ruby, database columns |
| kebab-case | hello-world | URLs, CSS classes, file names |
Title case is not just capitalising everything
Proper title case capitalises the first and last words and all major words, but leaves short articles, conjunctions and prepositions lowercase: "The Rise of the Machines", not "The Rise Of The Machines".
Style guides disagree on the details. AP style lowercases prepositions of three letters or fewer; Chicago lowercases all prepositions regardless of length. Both capitalise the first and last word no matter what. Pick one guide and apply it consistently.
Naming conventions by language
| Language | Variables | Classes | Constants |
|---|---|---|---|
| JavaScript / TypeScript | camelCase | PascalCase | UPPER_SNAKE |
| Python | snake_case | PascalCase | UPPER_SNAKE |
| Java | camelCase | PascalCase | UPPER_SNAKE |
| C# | camelCase | PascalCase | PascalCase |
| Go | camelCase | PascalCase (exported) | PascalCase |
| Rust | snake_case | PascalCase | UPPER_SNAKE |
| SQL | snake_case | — | — |
| CSS | kebab-case | — | — |
In Go, capitalisation is not stylistic — an identifier starting with an uppercase letter is exported from its package, and a lowercase one is not.
Why URLs use kebab-case
Search engines treat hyphens as word separators and underscores as word joiners, so /case-converter/ reads as two words while /case_converter/ may be read as one. Google has stated this explicitly.
Hyphens are also visually clearer in a URL, survive being underlined in a link, and avoid the encoding problems that spaces cause. Lowercase kebab-case is the standard for web paths, CSS class names and static asset file names.
Frequently asked questions
What is the difference between title case and sentence case?
Title case capitalises the major words in a heading — "The Rise of the Machines". Sentence case capitalises only the first word and any proper nouns — "The rise of the machines". Most modern interfaces use sentence case for buttons and labels.
What is camelCase?
A naming style where the first word is lowercase and each subsequent word is capitalised with no separators, as in getUserName. It is the standard for variables in JavaScript, Java and C#.
What is the difference between camelCase and PascalCase?
Only the first letter. camelCase starts lowercase (userName); PascalCase starts uppercase (UserName). PascalCase is conventionally reserved for classes, types and React components.
Should URLs use hyphens or underscores?
Hyphens. Search engines treat them as word separators and underscores as joiners, so word-counter reads as two words while word_counter may not.
Does converting case change my text?
Only capitalisation. Punctuation, spacing, line breaks and word order are preserved exactly, except in the programming styles which necessarily replace spaces with separators.
Can it handle accented characters?
Yes. Conversion is Unicode-aware, so accented Latin characters, Greek, Cyrillic and other cased scripts convert correctly.
Is my text uploaded?
No. Conversion happens entirely in your browser and nothing is transmitted.
What is UPPER_SNAKE_CASE for?
Constants, by near-universal convention across languages — MAX_RETRY_COUNT. It signals to other developers that the value is not meant to change.
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Case Converter is one of all the free tools on ToolNest. No account or subscription needed — anywhere in the world.