Case Converter

About Case Conversion

Case conversion is essential for writers, developers, and social media managers. Whether you need to format a headline in Title Case, convert variable names to camelCase or snake_case, or just fix text that was accidentally typed in CAPS LOCK, this tool handles it all instantly in your browser — no data leaves your machine, and nothing is sent to a server.

Case Types Explained

This tool supports a comprehensive range of case formats, each with its own conventions and typical use cases:

• UPPERCASE — Every character is capitalised. Used for shouting in text, acronyms (NASA, HTTP), CSS constants, and SQL keywords. Often called all caps.
• lowercase — No capital letters at all. Common in email addresses, URLs, and Unix command-line utilities where case-insensitive matching is preferred.
• Title Case — The first letter of every major word is capitalised. Standard for book titles, article headlines, and formal document headings.
• Sentence case — Only the first letter of the first word after each period (or the start of the text) is capitalised. The standard for body text in English prose.
• camelCase — Words are joined with no separator; the first word starts lowercase, and each subsequent word starts uppercase (e.g., myVariableName). The standard naming convention in JavaScript, TypeScript, Java, and C# for variables and function names.
• PascalCase — Like camelCase but the first word is also capitalised (e.g., MyClassName). Used for class names, constructors, React components, and C# / .NET type definitions.
• snake_case — Words are joined with underscores, all lowercase (e.g., my_variable_name). The standard in Python, Ruby, and Rust for variable and function names. Also used for CSS class names in BEM methodology and database column names.
• kebab-case — Words are joined with hyphens, all lowercase (e.g., my-variable-name). Preferred for URL slugs, HTML/CSS class names, file names in web projects, and Lisp-family languages.
• dot.case — Words are joined with periods, all lowercase (e.g., my.variable.name). Seen in configuration keys, property paths in JavaScript (lodash / object-path), and domain-specific notations.
• CONSTANT_CASE — All uppercase with underscores between words (e.g., MAX_RETRY_COUNT). The convention for global constants and environment variables in most programming languages.
• Train-Case — Like kebab-case but the first letter of every word is capitalised (e.g., My-Variable-Name). Occasionally used in HTTP header names and certain configuration formats.
• aLtErNaTiNg CaSe — Alternating uppercase and lowercase characters, often used for ironic or sarcastic emphasis in social-media text and memes.
• Inverse Case — Flips the case of each character: uppercase becomes lowercase and vice versa. Useful for quickly fixing text typed with the Caps Lock accidentally enabled.

When to Use Each Case

Choosing the right case convention makes your code more readable and your writing more professional. Here is a quick-reference guide:

• JavaScript / TypeScript — Use camelCase for variables, functions, and object properties; PascalCase for classes, interfaces, and React components; UPPER_SNAKE_CASE (CONSTANT_CASE) for global constants.
• Python / Ruby — Use snake_case for variables, functions, and method names; PascalCase for class names; UPPER_SNAKE_CASE for constants and environment variables.
• CSS / HTML — Use kebab-case for CSS class names and IDs (e.g., .main-header, #submit-btn); camelCase for JavaScript DOM properties like backgroundColor.
• URLs and SEO — Use kebab-case for URL slugs (e.g., /about-us, /how-to-install). Hyphens are treated as word separators by search engines, improving readability and ranking.
• Database columns — snake_case is the prevailing convention in SQL and ORM frameworks (e.g., user_id, created_at). Some teams prefer PascalCase for table names.
• File names — kebab-case for web assets (component-name.tsx, main-style.css); snake_case for data files (customer_report_2025.csv); PascalCase for React/component files (UserProfile.tsx).
• Social media and casual writing — Title Case for attention-grabbing headlines; Sentence case for natural blog post body text; UPPERCASE sparingly for emphasis; aLtErNaTiNg CaSe for ironic or humorous effect.

Pair this tool with our Lorem Ipsum Generator to produce placeholder text in your target case format, or use the Fake Data Generator to create realistic sample data already formatted the way you need it.