### Input Text Sample Live Preview _Enter your text here to convert between different cases..._ Statistics 0 Characters 0 Words 0 Lines 0 Sentences Convert Text Clear ### Converted TextLive Start typing text to see live conversions... # Free Case Converter - Convert Text to camelCase, snake_case, UPPERCASE & More Convert text between all 9 case formats instantly: UPPERCASE, lowercase, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, Title Case, and Sentence case - with live preview and one-click copy. ## What Is a Case Converter? A **case converter** (also called a text case changer or string case transformer) is a tool that reformats text between different capitalization styles. Each case style has a specific purpose in programming, writing, and design. Developers need to convert between cases constantly - a variable named in camelCase in JavaScript needs to become snake_case in Python, or CONSTANT_CASE in a configuration file. Writers need to switch between Title Case for headlines and Sentence case for body text. This tool converts your text into all nine standard case formats simultaneously, so you can copy whichever one you need. For a URL-ready version of a title, use the [Slug Generator](https://www.toolcomb.com/slug-generator). For repeated changes across a larger paste, open [Find and Replace](https://www.toolcomb.com/find-and-replace), then use [Diff Checker](https://www.toolcomb.com/diff-checker) to review the before-and-after text. ### All 9 Case Formats - When to Use Each | Case | Example | Primary Use | | --- | --- | --- | | UPPERCASE | HELLO WORLD | Constants, acronyms, emphasis, shouting in informal writing, database column names in SQL | | lowercase | hello world | HTML attributes, CSS class names (before kebab-case), email addresses, Unix filenames | | camelCase | helloWorld | JavaScript, TypeScript, Java variables and function names; JSON property keys; React props | | PascalCase | HelloWorld | Class names in most OOP languages (Python, Java, C#, TypeScript); React component names; C# methods | | snake_case | hello_world | Python variables and functions; Ruby; database column names; Linux/Unix file and directory names | | kebab-case | hello-world | HTML/CSS class names; URL slugs; npm package names; HTML data attributes; file names in web projects | | CONSTANT_CASE | HELLO_WORLD | Constants in Python (PEP 8); environment variables (.env files); configuration keys; Redux action types | | Title Case | Hello World | Article headlines; book titles; UI headings; product names; any formal heading in English writing | | Sentence case | Hello world | Body text, descriptions, tooltips, UI labels, informal headings, email subjects | ### Available Case Conversions UPPERCASE Convert all characters to uppercase Example: HELLO WORLD lowercase Convert all characters to lowercase Example: hello world camelCase First word lowercase, subsequent words capitalized, no spaces Example: helloWorld PascalCase All words capitalized, no spaces Example: HelloWorld snake_case Words separated by underscores, all lowercase Example: hello_world kebab-case Words separated by hyphens, all lowercase Example: hello-world CONSTANT_CASE Words separated by underscores, all uppercase Example: HELLO_WORLD Title Case First letter of each word capitalized Example: Hello World Sentence case First letter capitalized, rest lowercase Example: Hello world ### Frequently Asked Questions - Case Converter #### What's the difference between camelCase and PascalCase? camelCase starts with a lowercase letter (helloWorld), while PascalCase (also called UpperCamelCase) starts with an uppercase letter (HelloWorld). In JavaScript and TypeScript, camelCase is used for variables, functions, and object properties, while PascalCase is used for class names and React component names. #### When should I use snake_case vs kebab-case? snake_case (underscores) is the standard in Python (PEP 8 style guide) for variable and function names, and is widely used for database column names. kebab-case (hyphens) is standard in CSS class names, HTML attributes, URL slugs, and npm package names. The key difference: hyphens are valid in URLs and CSS but not in most programming language identifiers; underscores are valid in identifiers but not in URLs. #### What is CONSTANT_CASE used for? CONSTANT_CASE (SCREAMING_SNAKE_CASE) is the standard for constants - values that never change - in Python (PEP 8), environment variables (.env files), Redux action type strings, and configuration keys. In JavaScript/TypeScript, it signals to other developers that a value should not be reassigned. #### How does the converter handle special characters and punctuation? For programming cases (camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE), special characters and punctuation are removed since they are not valid in most programming language identifiers. For text cases (UPPERCASE, lowercase, Title Case, Sentence case), all characters including punctuation are preserved and only the capitalization changes. #### Can I convert multi-line text? Yes. Paste any amount of text - multi-line paragraphs, code snippets, or lists. The converter processes the entire input and shows results for all nine formats simultaneously. Use fullscreen mode for better visibility when working with large amounts of text. ## Related Tools Discover more free tools that might help with your next task. [HTML ↔ Markdown Converter Convert between HTML and Markdown Use Tool](https://www.toolcomb.com/html-markdown-converter) [Lorem Ipsum Generator Generate placeholder text for design and content Use Tool](https://www.toolcomb.com/lorem-ipsum-generator) [Regex Testing Test and validate regular expressions Use Tool](https://www.toolcomb.com/regex-testing) [Word Counter Count words, characters, and reading time instantly Use Tool](https://www.toolcomb.com/word-counter) [Cron Expression Generator Build and explain crontab schedules in plain English Use Tool](https://www.toolcomb.com/cron-expression-generator) [Diff Checker Compare two texts line by line in the browser Use Tool](https://www.toolcomb.com/diff-checker) ### Related guides Read the how-to, then come back to this tool when you are ready to run it locally. - [How to Generate URL Slugs for SEO and APIs Lowercase, hyphens, unicode pitfalls, stable IDs vs readable paths - generate slugs in the browser and pair with case conversion for code identifiers.](https://www.toolcomb.com/blog/how-to-generate-url-slugs) - [How to Convert Text Case: Title, Camel, Snake, and More Naming conventions and headlines, converted locally.](https://www.toolcomb.com/blog/how-to-convert-text-case) - [What Lorem Ipsum Is For (and How to Generate It) Placeholder text for mockups, generated locally.](https://www.toolcomb.com/blog/what-lorem-ipsum-is-for) [View All Tools](https://www.toolcomb.com/tools)