camelCase joins words without spaces, capitalising every word after the first. Example: 'hello world' becomes 'helloWorld'. It is widely used in JavaScript variable and function names.

snake_case replaces spaces with underscores and uses all lowercase letters. Example: 'hello world' becomes 'hello_world'. It is common in Python, Ruby, and database column names.

Title Case capitalises the first letter of each word. Example: 'the quick brown fox' becomes 'The Quick Brown Fox'. Used in headings and titles.

What is the difference between sentence case and title case?

Sentence case only capitalises the first word and proper nouns. Title Case capitalises every word. Both are useful in different writing contexts.

Can I convert programming variable names?

Yes — paste any text, select the target case convention, and convert. Useful for renaming variables between programming language conventions such as camelCase to snake_case.

Case Converter — UPPER, lower, Title, camelCase

Input text

Result

About the Case Converter

Text case conversion is needed constantly in software development, content editing, and data processing. Different naming conventions are required in different contexts: JavaScript variables use camelCase, database columns use snake_case, CSS classes use kebab-case, and constants use SCREAMING_SNAKE_CASE. Inconsistent casing in code or data pipelines can cause silent matching failures and hard-to-find bugs.

Naming conventions and their uses

camelCase — JavaScript variables and functions: myVariableName
PascalCase — class names in most languages: MyClassName
snake_case — Python variables, database columns: my_variable_name
kebab-case — CSS classes, HTML attributes, URL slugs: my-variable-name
SCREAMING_SNAKE_CASE — constants in Python, C, Java: MAX_RETRY_COUNT
Title Case — headings and proper nouns: My Document Title

Sentence case vs Title Case

Sentence case capitalises only the first word and proper nouns ("This is my heading"). Title Case capitalises the first letter of most words ("This Is My Heading"). Style guides differ: AP style capitalises major words; Chicago style capitalises all words except short prepositions and conjunctions.

Automatic case conversion in code

Most modern IDEs and code editors have built-in case conversion shortcuts. VS Code: select text, open Command Palette (Ctrl+Shift+P), type "Transform to". Vim: gU to uppercase, gu to lowercase, g~ to toggle. Sed: echo "TEXT" | sed 's/.*/\L&/' for lowercase.

VS Code — Command Palette > "Transform to Uppercase/Lowercase/Title Case"
Vim/Neovim — gU (uppercase), gu (lowercase), g~ (toggle) applied to any motion
Python — str.upper(), str.lower(), str.title(), str.capitalize()
JavaScript — str.toUpperCase(), str.toLowerCase(); no built-in title case; use a library

Frequently Asked Questions

What is the difference between camelCase and PascalCase?

Both join words without spaces and capitalise the first letter of each word, except camelCase starts with a lowercase letter (myVariableName) while PascalCase starts with an uppercase letter (MyVariableName). PascalCase is also called UpperCamelCase.

When should I use snake_case vs kebab-case?

Use snake_case in Python, Ruby, and SQL column names. Use kebab-case in CSS class names, HTML data attributes, URL slugs, and many REST API conventions. They are conceptually the same pattern but ecosystem convention matters for readability and tooling compatibility.

How do I convert to Title Case in JavaScript?

str.split(" ").map(w => w.charAt(0).toUpperCase() + w.slice(1).toLowerCase()).join(" "). For proper Title Case that respects short words like "a" and "the", you need a more nuanced implementation or a library like the title-case npm package.

Why do programming languages have different naming conventions?

Each language community developed conventions independently, and most languages have official style guides (PEP 8 for Python, Google Style Guides for Java and JavaScript). Consistency within a codebase matters more than which convention you choose.

How do I convert text to uppercase on the command line?

Linux/Mac terminal: echo "text" | tr '[:lower:]' '[:upper:]'. Python: "text".upper(). JavaScript: "text".toUpperCase(). In Microsoft Word: select text and press Shift+F3 to cycle through cases.