Text Case Converter

When to Use Each Case

Different programming languages and contexts have established conventions for naming. Using the wrong case in the wrong context does not break code in most cases, but it signals unfamiliarity with the ecosystem and can cause issues in case-sensitive systems.

Developer Naming Conventions

camelCase is the standard for JavaScript variables, functions, and JSON keys. PascalCase (also called UpperCamelCase) is used for class names and component names in JavaScript, TypeScript, and C#. snake_case is the Python convention for variables and functions, and is also used in Ruby and SQL column names. kebab-case is used for CSS class names, HTML attributes, URL slugs, and file names in most web projects. CONSTANT_CASE (also called SCREAMING_SNAKE_CASE) is the convention for constants and environment variables across most languages. Use our URL Encoder if you need to encode kebab-case slugs for use in query strings.

Title Case vs Sentence Case

Title case capitalises the first letter of every word and is used for headings, titles, and proper nouns. Sentence case capitalises only the first word and proper nouns, mirroring normal sentence structure. Most style guides (APA, Chicago, MLA) have specific rules about which words to capitalise in title case — this tool uses a simplified approach that capitalises every word, which is appropriate for code and UI labels. For editorial content, verify against your style guide.

Frequently Asked Questions

What is the difference between camelCase and PascalCase?

Both join words without spaces, but they differ in where the first letter is capitalised. camelCase starts with a lowercase letter and capitalises the first letter of each subsequent word: helloWorld. PascalCase capitalises the first letter of every word including the first: HelloWorld. JavaScript uses camelCase for variables and functions, PascalCase for classes and React components.

When should I use snake_case vs kebab-case?

snake_case uses underscores and is the standard in Python, Ruby, and SQL. kebab-case uses hyphens and is standard in CSS, HTML, and URL slugs. The practical difference is that hyphens are not valid in most variable names in programming languages (they would be interpreted as a minus operator), while underscores are. In CSS and HTML, hyphens are preferred because they do not conflict with any syntax.

Does this tool handle special characters and punctuation?

For programmer cases (camelCase, snake_case, kebab-case, etc.), the converter strips punctuation and treats it as a word boundary. For example, "hello-world! foo" becomes helloWorldFoo in camelCase. For display cases (uppercase, lowercase, title case, sentence case), punctuation is preserved as-is. Accented characters and Unicode letters are preserved in all cases.

What is CONSTANT_CASE used for?

CONSTANT_CASE (also called SCREAMING_SNAKE_CASE) is the widely-adopted convention for values that should not change — environment variables (DATABASE_URL), named constants in most languages (MAX_RETRIES), and enumeration values. It is supported in Python, JavaScript, Java, C, Go, and most other languages. The all-caps with underscores convention immediately signals to readers that a value is a constant rather than a variable.

How does sentence case work?

Sentence case capitalises only the first character of the entire string and lowercases everything else, mirroring how a normal English sentence is written. It does not attempt to detect or preserve proper nouns — those would need to be capitalised manually after conversion. It is useful for normalising text that has been written in all-caps or inconsistently capitalised.