Case Converter
Paste or type text and convert it live to UPPERCASE, lowercase, Title Case, Sentence case, or developer naming styles like camelCase, PascalCase, snake_case and kebab-case, then copy the result in one click. Everything runs locally in your browser; your text is never uploaded. Chinese, Japanese and Korean characters have no case and are kept as-is.
- Modes
- Case styles + developer naming
- Conversion
- Live output · no buttons
- Privacy
- Nothing uploaded
- Usage
- Free · no sign-up
Characters 0 · Words 0
Characters 0 · Words 0
Why you need it
For headlines, copywriting and variable names
Case looks like a small thing until you have to fix it by hand: retyping is slow and error-prone. Paste it here and it is done in one click.
Basic case in one click
Fix text typed with Caps Lock on, or turn a heading into ALL CAPS for posters and banners — paste, click, done. No retyping, nothing missed.
Title Case & Sentence case
Title Case capitalizes every English word for headlines and book titles; Sentence case keeps only the first letter of each sentence capitalized — perfect for tidying hastily written English.
Developer naming styles
Convert between camelCase, PascalCase, snake_case and kebab-case for variables, class names, CSS classes and config keys while coding or wiring up APIs.
CJK-safe conversion
Chinese, Japanese and Korean characters have no case and are preserved in every mode; apostrophes and hyphens are handled correctly — "don't" becomes "Don't", never "Don'T".
Converts as you type
No "convert" button: the result pane updates live with your input and switching modes applies instantly. Character and word counts update alongside.
Runs fully local
Text never leaves your browser, the tool works offline, and no requests are made while the input is empty.
Details worth knowing about case conversion
Case conventions differ from one context to another — knowing the rules keeps you from awkward headlines or broken variable names.
What is the difference between the four basic case styles?
ALL CAPS suits headings, warnings and acronyms (NASA); all lowercase is common in modern branding and UI copy; Title Case capitalizes the first letter of each word and is the convention for English headlines and book titles; Sentence case mirrors normal prose.
This tool applies "capitalize each word, lowercase the rest" for Title Case, and lowercases everything first for Sentence case, then re-capitalizes after sentence boundaries.
Where are camelCase, PascalCase, snake_case and kebab-case used?
camelCase (myVariableName) is the convention for JavaScript and Java variables and functions; PascalCase (MyClassName) for classes and components; snake_case (my_variable_name) for Python/Ruby variables and database columns; kebab-case (my-variable-name) for CSS classes, URLs and HTML attributes.
When wiring up APIs or organizing configs, convert first and tweak second — much faster than retyping.
How are words split for the developer styles?
Spaces, punctuation, underscores and hyphens all act as separators, and existing camelCase/PascalCase text is split at uppercase boundaries. Letter–digit runs stay intact: "v2" and "html5" remain one word.
So both "user_nickname" and "userNickname" convert cleanly to "user-nickname"; a run of CJK characters is kept as a single word.
How is this different from CSS text-transform?
CSS text-transform: uppercase only changes how text looks — copying it or reading it back returns the original. This tool changes the text itself, so what you copy is what you get.
Use CSS for visual-only styling; use this tool when the result goes into code, databases or documents.
What happens to Chinese text?
CJK characters have no case, so every mode leaves them untouched.
Only the Latin part changes: "我爱 Open Source" becomes "我爱 OPEN SOURCE" in UPPERCASE, and the Chinese run joins as a single word in snake_case.
FAQ
Is my text uploaded or saved anywhere?
No. All conversion happens in your browser with JavaScript — no request ever carries your text anywhere, it works offline, and everything is gone once you refresh the page.
Should I pick Title Case or Sentence case?
Use Title Case for headlines, article and book titles. Use Sentence case to fix prose typed in ALL CAPS or with random capitalization — it lowercases everything first and keeps only each sentence opener capitalized.
Will ALL-CAPS text split correctly into camelCase?
Word splitting for developer styles relies on case boundaries, so consecutive capitals have no boundary: "HTTPSERVER" stays one word. For all-caps multi-word text, run Sentence case first and then convert; mixed forms like "userName" or "user_name" split correctly.
Why does the output lose the original spacing?
Only the developer styles rearrange text: they keep just the words and join them with a fixed separator. UPPERCASE, lowercase, Title Case and Sentence case preserve all spaces and punctuation exactly.
Is there a length limit? Does it work on mobile?
There is no limit — paste whole documents if you like. Very long text (hundreds of thousands of characters) may feel slightly laggy on low-end devices because the result recomputes as you type. The layout is responsive; the two panes stack vertically on small screens.