Case Converter

Case conversion means changing text from one letter-case style to another — for example, from snake_case (common in Python) to camelCase (standard in JavaScript and TypeScript). Different programming languages, frameworks, and file formats expect different case conventions. Using the wrong one causes lint errors, broken APIs, and code that looks foreign to the rest of the codebase.

Common case styles

Style	Example	Used in
lowercase	hello world	Plain text, filenames
UPPERCASE	HELLO WORLD	Acronyms, headings
Title Case	Hello World	Headlines, book titles
Sentence case	Hello world	Body text, descriptions
camelCase	helloWorld	JavaScript, Java, Go variables
PascalCase	HelloWorld	React components, C# classes
snake_case	hello_world	Python, Ruby, SQL
kebab-case	hello-world	CSS classes, URLs, HTML attributes
CONSTANT_CASE	HELLO_WORLD	Constants, env vars

When case conversion matters

API integration: Your Python backend sends user_id in JSON. Your JavaScript frontend expects userId. Converting between snake_case and camelCase is the most common cross-language case problem.

CSS class naming: kebab-case is the universal standard for CSS (background-color, font-size). Using camelCase in CSS works syntactically but fights every framework and methodology.

URL design: Hyphens are the standard word separator in URLs. Google treats hyphens as word separators but underscores as joiners — so /case-converter is read as two words, while /case_converter is read as one.

Database column naming: PostgreSQL folds unquoted identifiers to lowercase, making UserId and userid identical. snake_case avoids this ambiguity and is the PostgreSQL community convention.

How this tool works

Type or paste text above. Every case variant appears instantly — no submit button, no page reload. Click Copy on any row to copy that variant to your clipboard. All processing runs locally in your browser. No text is ever uploaded.