Case Converter
Convert text to UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case or kebab-case, all at once.
UPPERCASE
—
lowercase
—
Title Case
—
Sentence case
—
camelCase
—
snake_case
—
kebab-case
—
- Free — No signup required
- Instant — Results update as you type
- Private — Processed in your browser
Renaming a variable, fixing a heading someone typed in caps lock, turning a title into a URL slug — they are all the same operation, and doing it by hand is tedious and error-prone. The converter above shows your text in all seven common cases at once, each with its own copy button.
How it works
Type or paste your text. Seven results appear and update as you type:
| Case | Hello World Example becomes |
|---|---|
| UPPERCASE | HELLO WORLD EXAMPLE |
| lowercase | hello world example |
| Title Case | Hello World Example |
| Sentence case | Hello world example |
| camelCase | helloWorldExample |
| snake_case | hello_world_example |
| kebab-case | hello-world-example |
The first four preserve your original spacing and punctuation and only change letter case. The last three are identifier formats, so they take a different route: the input is first split into words — on whitespace, on any punctuation, and on camelCase boundaries — then lowercased and rejoined with the right separator.
That tokenising step is what makes the tool round-trip properly. Hello World, hello-world and helloWorld all normalise to the same two words, so you can paste a name in any of the three forms and get the other two back. Punctuation is dropped in identifier formats, because user.name! is not a legal identifier in most languages.
Sentence case lowercases everything and then capitalises the first letter of the string and the first letter after each ., ! or ? followed by a space. It does not know about proper nouns — "paris" stays lowercase — and it does not know about abbreviations, so "e.g. this" gets a capital after the second dot. Check the output on anything longer than a paragraph.
Title Case capitalises every whitespace-separated word. Editorial style guides usually keep short articles and prepositions lowercase ("The Lord of the Rings"), and the tool does not, because the list of exceptions differs between style guides. Fix those by hand.
Everything happens in your browser; the text you paste is never sent anywhere.
Which case where
Conventions are not arbitrary — each language community settled on one, and consistency inside a codebase matters far more than which one you pick.
- camelCase — Java and JavaScript variables, methods and fields; JSON keys in most JavaScript-facing APIs.
- PascalCase — classes and types in Java, C# and TypeScript. This tool does not emit it directly; take the camelCase output and capitalise the first letter.
- snake_case — Python identifiers, Ruby, and SQL table and column names. Database identifiers are often case-folded by the server, which is why snake_case survives round trips that camelCase does not.
- kebab-case — URL slugs, CSS class names, HTML attributes, CLI flags and file names. It cannot be used for identifiers in most languages because the hyphen reads as subtraction.
- UPPER_SNAKE_CASE — constants and environment variables. Take the snake_case output and uppercase it.
The Java conventions, and why they are worth following even when you disagree with them, are covered in Java coding standards. Where the same names cross into a schema, database design and normalization covers naming that stays legible after a few years of change.
Related tools
For counts, reading time and character limits on the same text, use the word counter. For filler text to test a layout with, the lorem ipsum generator. To percent-encode a slug for use in a query string, the URL encoder/decoder.
FAQ
- What's the difference between Title Case and Sentence case?
- Title Case capitalizes the first letter of every word (used in headings); Sentence case only capitalizes the first letter of each sentence, like normal prose.
- How does the converter decide where words start in camelCase or snake_case?
- It splits on spaces, punctuation, and existing case changes, so "Hello World", "hello-world" and "helloWorld" all convert to the same set of words before reformatting.
- Is this useful for programming variable names?
- Yes — camelCase, snake_case and kebab-case are common variable, file and CSS-class naming conventions across different languages and style guides.