Case Converter

Fix the case without retyping the paragraph

A pasted title in ALL CAPS, a variable name that needs camelCase, and a sentence that lost its capitals after a bad export are the same chore: you should not retype 400 words to change case. This case converter takes your text and applies uppercase, lowercase, title case, sentence case, camelCase, or snake_case in the browser.

Keep the original in the input and read the output next to it so you can copy only when the result looks right. Programmatic cases destroy spacing on purpose; prose cases do not.

What each mode does

Uppercase and lowercase use the Unicode case mapping your browser already knows, so most accented Latin letters behave. Title case capitalizes each whitespace-separated word. Sentence case uppercases the first letter of the text and letters that follow end punctuation, then lowercases the rest—good enough for sloppy exports, imperfect for “iPhone” and “McDonald.”

camelCase and snake_case tokenize on spaces, hyphens, underscores, and other non-alphanumeric separators. camelCase writes helloWorld. snake_case writes hello_world. They are for identifiers, not novels. Running a full paragraph through snake_case will produce a very long identifier; that is expected.

How to use it

Paste, pick a mode, copy the output. If you also need a word count, copy first and open the word counter—converting to camelCase will smash the count to one “word.” If you need a QR of a converted slug, generate the slug here, then paste it into the QR tool.

For passwords, do not use this page. Case conversion is deterministic. Use the password generator, which draws from the system CSPRNG.

Examples

“the quick brown fox” in title case becomes “The Quick Brown Fox.” In sentence case it becomes “The quick brown fox.” In camelCase it becomes theQuickBrownFox. In snake_case it becomes the_quick_brown_fox.

“XMLHttpRequest” already has internal capitals. Tokenizing that string is ambiguous; the converter will not perfectly “understand” the acronym. For code, prefer converting human phrases into identifiers, not the other way around.

Style guides versus buttons

Newspapers leave short prepositions lowercase in headlines. This tool does not load a dictionary of small words, because users who want that usually want a human editor more than a checkbox. If you are publishing, read the output.

Everything stays on the device. A confidential product name in the box is not our dataset.

Typical examples

Frequently asked questions

What is title case?

This tool capitalizes the first letter of each word and lowercases the rest. It is a simple title case, not the Chicago-style list of small words left lowercase.

How do you make camelCase?

Words are split on spaces, punctuation, and underscores. The first word is lowercased and later words are capitalized with no separators: “hello world” → helloWorld.

What is snake_case used for?

Programming identifiers, file names, and some databases. The converter lowercases tokens and joins them with underscores.

Will this change my curly quotes or emoji?

Letters change case. Emoji and most punctuation stay. Underscores and spaces may be consumed when you pick camel or snake case.

Is the text uploaded?

No. Conversion is local.