Text Case Converter

Text Case Converter: Nine Formats, One Click

Paste any text above and convert it to UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, or CONSTANT_CASE instantly. This text case converter handles edge cases that trip up naive tools: acronyms like API and HTML, contractions like don't and it's, mixed-input with inconsistent original formatting, and Unicode characters with language-specific capitalization rules. Select the target format, click convert, and copy the result directly into your code editor, CMS, or document.

Convert Text to Lower Case and Upper Case

The most common conversion is fixing accidental Caps Lock. You typed three paragraphs before noticing the key was on - rather than deleting and retyping, paste the ALL-CAPS text here and convert text to lower case in one click. The reverse operation, convert text to upper case, is useful for generating headings, acronym lists, and SQL keywords that convention demands be capitalized. Sentence case capitalizes only the first letter after each sentence-ending punctuation mark (period, exclamation, question mark) and lowercases everything else, handling paragraph-level reformatting that manual editing would take minutes to complete.

Programming Naming Conventions by Language

camelCase is standard for variables and functions in JavaScript, Java, TypeScript, Swift, and Kotlin: let userName, function getProfile(). PascalCase (UpperCamelCase) is the convention for class names, React components, and type definitions: class UserProfile, interface DataResponse. snake_case dominates Python, Ruby, Rust, and database column names: user_name, get_profile(), created_at. kebab-case is the standard for CSS class names, HTML attributes, URL slugs, and CLI flags: class="user-profile", --max-retries, /blog/my-first-post. CONSTANT_CASE (screaming snake case) marks constants and environment variables across nearly all languages: MAX_RETRIES, API_KEY, DATABASE_URL. Using the wrong convention violates linting rules, makes code harder to search and refactor, and signals unfamiliarity with the ecosystem to reviewers. This online text case converter translates between all five programming conventions so you can port naming schemes across language boundaries without manual rewriting.

Title Case Rules and Style Guide Variations

Title Case capitalizes major words while keeping minor words (a, an, the, and, but, or, in, on, at, to, for, of, by) lowercase unless they begin or end the title. Different style guides disagree on details. AP lowercases prepositions under four letters but capitalizes longer ones. Chicago Manual of Style lowercases all prepositions regardless of length. APA capitalizes any word of four or more letters. The short verb "is" should always be capitalized (it is a verb, not a preposition, despite its length). The case text converter follows the most common convention but no automated tool perfectly handles every edge case, so verify against your specific style guide for formal publishing, academic submissions, and brand guidelines where deviations are visible and consequential.

Bulk Reformatting and Content Migration

When migrating data between systems that store text in different case conventions, the converter saves hours of manual editing. A legacy CRM that stored customer names in ALL CAPS can be converted to proper Title Case before importing into a modern system that expects standard capitalization. Database columns exported in camelCase can be converted to snake_case for a Python project. SEO slug fields in Title Case can be reformatted to kebab-case for clean URL generation. File names with spaces and mixed case can be converted to snake_case or kebab-case for consistent, command-line-friendly naming. Paste the batch, convert, and copy - the tool handles line-by-line conversion so multi-line lists maintain their structure after transformation.

Case Sensitivity Across Systems

Understanding where case matters prevents hard-to-debug errors. JavaScript variables are case-sensitive: userName and username are different identifiers. SQL keywords are case-insensitive but table and column names may be case-sensitive depending on the database engine and operating system (MySQL on Linux is case-sensitive for table names, MySQL on Windows is not). File systems diverge: Linux treats File.txt and file.txt as different files; macOS and Windows treat them as the same. URLs are case-sensitive in the path component (example.com/Page and example.com/page are different resources) but case-insensitive for the domain name. Email local parts (before the @) are technically case-sensitive per RFC 5321 but virtually every mail server ignores case in practice. Knowing which systems respect case and which ignore it helps you choose the right convention from the start rather than discovering conflicts after deployment.

Text Case Converter Online vs IDE Features

VS Code offers Transform to Uppercase/Lowercase/Title Case through the Command Palette (Ctrl+Shift+P). Sublime Text has similar shortcuts. These work well for selected text within a file but do not support programming case conversions (camelCase, snake_case, kebab-case) without extensions. The text case converter online here covers all nine formats from a single interface, handles multi-line input, and requires no installation or configuration. Use the IDE shortcut for quick in-file toggling between upper and lower; use this tool when you need programming case conversions, batch processing of pasted lists, or access from a machine where your usual editor is not available.

Frequently asked questions