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Case Converter

Convert text between UPPERCASE, Title Case, camelCase, snake_case and more β€” instantly in your browser.

Privacy: your files never leave your device. All processing happens locally in your browser.

How to use

  1. 1.Type or paste your text into the input box.
  2. 2.See all ten case and naming-convention variants generated instantly below.
  3. 3.Click Copy next to any result to put that version on your clipboard.

About Case Converter

Case Converter turns any block of text into every common capitalization and naming style at once. Paste a sentence, a heading, or a variable name and you instantly see ten variants side by side, each with its own copy button. Everything is computed locally in your browser, so nothing is ever uploaded β€” it works offline and handles large pastes without a round trip to a server.

The writing styles cover everyday text. Title Case capitalizes the first letter of every word for headlines and article titles. Sentence case capitalizes only the first letter of each sentence β€” split on periods, question marks, and exclamation points β€” which is the correct style for body copy and UI labels. UPPERCASE and lowercase are the quick fixes for text that arrived shouting or stuck on caps lock.

The naming styles cover programming conventions, where capitalization is not cosmetic but syntactic. camelCase (helloWorld) is standard for JavaScript and Java variables and functions. PascalCase (HelloWorld) names classes, React components, and types. snake_case (hello_world) is the Python and SQL convention for variables and column names. kebab-case (hello-world) is used for URLs, CSS classes, and file names. CONSTANT_CASE (HELLO_WORLD) marks environment variables and compile-time constants. Converting between them by hand is error-prone; a single wrong letter breaks the code.

What makes the naming conversions reliable is the word-boundary detection. The tool doesn't just swap spaces for underscores β€” it re-tokenizes the input first. It splits on spaces, underscores, hyphens, and punctuation, and it also detects camelCase and PascalCase boundaries, so fooBar_baz-qux is correctly understood as four words (foo, Bar, baz, qux) no matter which style it arrived in. That means you can paste a snake_case name and get clean camelCase back, or paste a messy mix of separators and still get a consistent result. Digits stay attached to their word, so order66 is treated as a single token rather than being split.

A subtle detail is how each style treats letters that were already capitalized. The naming conversions normalize every word to a single canonical form, so a shouting SNAKE_CASE constant pasted in becomes clean camelCase rather than a broken hybrid, and an acronym-heavy PascalCase identifier like HTMLParser is tokenized at the acronym boundary into HTML and Parser before being re-cased. The alternating style, by contrast, flips letters position by position and skips over spaces and punctuation so the visual zig-zag lands only on the letters. Because the rules are explicit and deterministic, the same input always produces the same output, which matters when you are scripting names or reformatting a column of data.

Common uses: fixing headline capitalization, renaming variables to match a team's style guide, converting API field names between JSON (camelCase) and a database (snake_case), turning a title into a URL slug (kebab-case), normalizing environment variable names to CONSTANT_CASE, and generating aLtErNaTiNg text for a bit of fun. Type once and every style is ready to copy β€” no sign-up, no upload, no waiting.

Frequently asked questions

What is the difference between Title Case and Sentence case?
Title Case capitalizes the first letter of every word (Hello World), which suits headlines. Sentence case capitalizes only the first letter of each sentence and lowercases the rest (Hello world), which is correct for body copy. This tool splits sentences on periods, question marks, and exclamation points.
How does it convert snake_case to camelCase and other naming styles?
The tool first re-tokenizes your input into words, splitting on spaces, underscores, hyphens, punctuation, and camelCase boundaries. It then re-joins those words in the target style. So fooBar_baz-qux becomes fooBarBazQux (camelCase) or foo_bar_baz_qux (snake_case) reliably, regardless of the input format.
Is my text uploaded anywhere?
No. All conversions run entirely in your browser using JavaScript. Your text never leaves your device and is never sent to a server, so it works offline and is safe for private or sensitive content.

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