Case Converter — UPPER, lower, camelCase, snake_case & More

camelCase (e.g. myVariableName) is the standard for variable and function names in JavaScript, Java, and Swift. The first letter is lowercase and each subsequent word starts with uppercase. PascalCase (e.g. MyClassName) capitalizes every word including the first, and is used for class names in most object-oriented languages — JavaScript, TypeScript, C#, Java, and PHP all follow this convention for class definitions. Mixing up the two is a common source of naming inconsistencies in codebases.

snake_case (e.g. user_first_name) uses underscores as word separators and is the dominant convention in Python for variables and functions, Ruby, and SQL column names. Database schemas almost universally use snake_case for table and column identifiers. kebab-case (e.g. my-component-name) uses hyphens and is the standard for CSS class names, HTML attributes, and URL path segments. File names for web assets (images, scripts, stylesheets) are also conventionally kebab-case in most frontend projects.

CONST_CASE (also called SCREAMING_SNAKE_CASE, e.g. MAX_RETRY_COUNT) is used for constants and environment variable names across most languages. In JavaScript and TypeScript, top-level const declarations that hold fixed configuration values are written in CONST_CASE. In Python, module-level constants follow the same convention per PEP 8. Environment variables in .env files and CI/CD pipelines are always CONST_CASE (e.g. DATABASE_URL, API_SECRET_KEY), making this format essential for DevOps and configuration management.

REST APIs and databases often return data in snake_case (e.g. first_name, created_at), while JavaScript frontend code expects camelCase (firstName, createdAt). When consuming third-party APIs or migrating between stacks, you may need to bulk-rename dozens of field names. This case converter lets you paste a list of snake_case field names and convert them all to camelCase at once, then use the results in your interface layer or data mapper.

Form inputs and user-generated content arrive in inconsistent case formats. A title typed as "my AWESOME product NAME" needs to become "My Awesome Product Name" for display, or "my-awesome-product-name" for a URL. Converting user input to a consistent case before storing it prevents duplicates in databases, ensures consistent display across pages, and simplifies search and filtering logic. Run user-submitted labels, tags, and category names through a case converter before persisting them.

Blog post titles, product names, and page headings need to be converted to URL-safe kebab-case slugs for use in routes and permalinks. A title like "10 Best Practices for REST APIs" becomes "10-best-practices-for-rest-apis". This conversion involves lowercasing, replacing spaces and special characters with hyphens, and removing punctuation — all of which the kebab-case conversion mode handles automatically. Combine with the Text to Slug tool for full accented-character normalization.