Case Converter
Convert text to uppercase, lowercase, title, camelCase, snake_case, and more, instantly.
Best for English/number text. Grab each result with its copy button.
The seven formats and how each one is built
Paste any text and it is converted at once into seven forms, each following a specific rule. UPPERCASE turns every letter capital and lowercase turns every letter small, which are simple character swaps. Title Case capitalizes the first letter of each word. Sentence case lowercases everything, then capitalizes the first letter of the text and the first letter after each period, question mark, or exclamation mark. The three programming formats first split your text into words at spaces, hyphens, underscores, periods, and lowercase-to-uppercase jumps (so userID splits into user and ID), then rejoin them: camelCase writes the first word lowercase and capitalizes the start of every following word with no separators (myVariableName), snake_case joins words with underscores in lowercase (my_variable_name), and kebab-case joins them with hyphens in lowercase (my-variable-name). A copy button sits next to each result so you never have to select text by hand.
A worked example
Suppose you paste the phrase user profile image URL. UPPERCASE returns USER PROFILE IMAGE URL and lowercase returns user profile image url. Title Case returns User Profile Image Url, and Sentence case returns User profile image url. On the code side, camelCase produces userProfileImageUrl, snake_case produces user_profile_image_url, and kebab-case produces user-profile-image-url. Notice that the tool treated URL as a normal word and lowercased it inside the code formats, so if you need the acronym preserved you would fix it manually afterward. Seeing all seven side by side makes it obvious which form fits where you are pasting it.
When and why to reach for it
- Coding: rename a batch of variables, functions, CSS classes, or database columns into the one convention a project uses, such as camelCase for JavaScript, snake_case for Python, or kebab-case for HTML attributes and URLs.
- Writing and publishing: clean up an English headline or button label into consistent Title Case, or fix an all-caps sentence that a colleague pasted into a document.
- Data cleanup: normalize a column of names, tags, or categories that arrived with mixed casing so that Apple, APPLE, and apple all become one comparable value before you sort or deduplicate.
Title Case, Sentence case, and real style rules
The tool applies a simple, predictable Title Case: it capitalizes the first letter of every word. That is fine for most quick jobs, but published style guides are stricter. Chicago, AP, and APA all keep short words like a, an, the, of, and, to, and in lowercase unless they start or end the title. So while the tool gives you The Rise And Fall Of Rome, an editor following AP or Chicago style would write The Rise and Fall of Rome, with the short joining words lowercased. Use the output as a fast first pass, then adjust the small joining words if you are following a formal style guide.
Common mistakes and misconceptions
- Expecting acronyms to survive: NASA and URL are treated as ordinary words (Nasa, url), and a mixed-case one like iOS is even split at the internal capital (I Os in Title Case). Scan the result and fix these by hand.
- Assuming word boundaries are detected by meaning: the splitter works on spaces, hyphens, underscores, periods, and lowercase-to-uppercase jumps. That handles userID → user_id nicely, but a string with no such signal, like userid2value, stays one block — add separators yourself first.
- Feeding it text that has no case: many scripts, including Korean, Japanese, Chinese, and Arabic, have no uppercase or lowercase, so those characters pass through unchanged; only letters with a case distinction (Latin, and also Greek or Cyrillic) are converted.
- Trusting the output for names with internal capitals: McDonald or LaTeX get split at each capital (Mc Donald, La Te X in Title Case), so proofread proper nouns.
Limits and how your text is handled
This is a formatting helper, not a grammar or style checker. It will not add commas, fix spelling, decide which words in a title should stay lowercase, or understand that a particular string is a brand name. For anything beyond mechanical case rules you still need a human eye. On privacy, the important point is that everything happens locally: your text is converted by JavaScript inside your own browser and is never uploaded to, logged by, or stored on any server. That means you can safely paste unpublished copy, internal variable names, or private notes without them leaving your device.
The text you enter is converted only in your browser and is never sent to or stored on a server.
Read the Privacy Policy →Frequently asked questions
What is the difference between Title Case and Sentence case?
Title Case capitalizes the first letter of every word, so the quick brown fox becomes The Quick Brown Fox. Sentence case lowercases the text and capitalizes the first letter of each sentence (the start of the text and after a period, question mark, or exclamation mark), so the same input becomes The quick brown fox. Use Title Case for headings and labels, and Sentence case for normal running text or when a style guide asks for it.
When should I use camelCase, snake_case, or kebab-case?
It depends on the language and place. camelCase (myVariableName) is standard for JavaScript and Java variables and functions. snake_case (my_variable_name) is common in Python, Ruby, and database column names. kebab-case (my-variable-name) is used for URLs, file names, and CSS class names, since underscores and capitals are awkward in web addresses.
Why did my acronym like URL or iOS get changed?
The converter treats every group of letters between boundaries as an ordinary word, so it has no way to know URL or NASA is an acronym, and a mixed-case one like iOS is even split at the lowercase-to-uppercase jump (i + OS). Title Case and the code formats will lowercase or re-capitalize the pieces like any other word. Just review the output and restore the acronym manually where you need it.
Can it split words that are joined with no space, like userIDvalue?
Partly. The tool splits at lowercase-to-uppercase jumps as well as spaces, hyphens, underscores, and periods, so userIDvalue becomes user_idvalue in snake_case — the jump between user and ID is detected, but IDvalue stays together because there is no signal inside it. For a clean three-word split, add separators first: user ID value converts to user_id_value.
Does it work with non-English text like Korean or Chinese?
Those scripts have no concept of uppercase and lowercase, so their characters pass through unchanged. Only letters with a case distinction (Latin, plus scripts like Greek and Cyrillic) are affected by the case rules. You can still paste mixed text; the English parts will convert while the rest stays exactly as you typed it.
Is my text sent anywhere or saved?
No. All conversion runs entirely in your browser using JavaScript, and the text you paste is never sent to or stored on any server. You can safely use it for private, internal, or unpublished content because nothing leaves your device.