Understanding Text Cases
Text case refers to how letters are capitalized in a string. Different contexts demand different cases: a headline uses Title Case, a Python variable uses snake_case, a Java method uses camelCase, and a constant uses UPPER_CASE.
The rules aren't always obvious. Title Case capitalizes major words but leaves articles ("the," "a," "an") and short prepositions ("in," "of," "at") lowercase, unless they're the first or last word. Sentence case capitalizes only the first word and proper nouns. These rules vary by style guide (AP, APA, Chicago all differ slightly).
For programming cases: camelCase joins words with no separator, capitalizing each word after the first. PascalCase is the same but capitalizes the first word too. snake_case uses underscores. kebab-case uses hyphens. CONSTANT_CASE is snake_case in all caps. Each language and framework has conventions about which to use where.
When to Use Each Case
Converting variable names between languages
Moving code from Python (snake_case) to JavaScript (camelCase)? Paste your variable names and convert them instantly instead of manually rewriting each one.
Formatting headlines and titles
Writing blog posts, email subjects, or presentation slides? Title Case makes headings look professional. Paste your text and get properly capitalized titles following standard rules.
Fixing accidentally typed caps lock text
Typed a whole paragraph in CAPS LOCK? Convert it to sentence case in one click instead of retyping everything.
Creating CSS class names or file names
CSS uses kebab-case for class names. File systems often prefer kebab-case or snake_case. Convert your descriptive text into the right format for your context.
Case Conversion Tips
Title Case rules vary by style guide
AP style capitalizes words of 4+ letters. APA capitalizes words of 4+ letters plus all "major" words. Chicago capitalizes everything except articles, prepositions, and conjunctions. This tool uses a common-sense approach that works for most contexts.
Acronyms can be tricky in camelCase
Should "HTTP request" become "httpRequest" or "HTTPRequest"? Conventions vary. Google's style guide recommends "httpRequest" (treat acronyms as words). This tool follows that convention.
Special characters are handled differently per case
In snake_case, spaces become underscores but existing underscores are preserved. In camelCase, all separators (spaces, hyphens, underscores) are removed and the next letter is capitalized. Numbers are kept as-is in all cases.
Limitations
- Title Case uses basic rules (capitalize first letter of each word). Does not follow AP, Chicago, or APA style guides for articles/prepositions.
- Cannot handle proper nouns intelligently — "new york" becomes "New York" in title case, but it cannot distinguish proper nouns from common words.
- Unicode case conversion follows JavaScript locale-independent rules. Special cases like Turkish İ/i mapping may not be handled correctly.
- Does not support programmable case patterns (custom regex-based transformations).
Features
- Convert to UPPERCASE, lowercase, Title Case, Sentence case
- Programming cases: camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE
- One-click conversion with instant preview
- Special characters and numbers handled correctly
- Copy result to clipboard with one click
- No data sent to any server. Runs entirely in your browser
Frequently Asked Questions
What text cases are supported?
The tool supports: UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, and dot.case. These cover virtually all common use cases in writing and programming.
Does it handle special characters and accented letters?
Yes. Accented characters (é, ñ, ü) are preserved and their case is changed correctly. Special characters like punctuation, numbers, and symbols are kept as-is. Only letters have their case modified.
Can I convert code variable names between languages?
Absolutely. Paste a snake_case Python variable like "user_first_name" and convert it to camelCase "userFirstName" for JavaScript, or PascalCase "UserFirstName" for C# classes. The tool correctly splits on underscores, hyphens, spaces, and camelCase boundaries.
How does Title Case decide which words to capitalize?
Articles (a, an, the), short conjunctions (and, but, or), and short prepositions (in, on, at, to, for) stay lowercase unless they're the first or last word. All other words are capitalized. This follows the most common style guide conventions.
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All text conversion happens entirely in your browser. No data is uploaded to any server. Your text never leaves your device.
In-Depth Guide
Text Case Conventions: camelCase, snake_case, and When to Use Each
Naming conventions encode meaning. This guide covers every common text case, which languages prefer which, and the pitfalls of automated conversion.
Read guideTips & Related Workflows
- Count words and characters in your converted text with the Word Counter.
- Test regex patterns for case-sensitive matching with the Regex Tester.
- Compare original vs converted text side by side with the Diff Checker.
- Format JSON keys to camelCase or snake_case conventions using the JSON Formatter.