About the Case Converter
Paste any text and the Case Converter rewrites it in the letter case you pick: UPPERCASE, lowercase, Title Case, Sentence case, or one of the naming styles programmers use, such as camelCase, snake_case and kebab-case.
It is handy whenever text arrives in the wrong shape. A headline typed in capitals, a list of product names that needs consistent capitalization, a spreadsheet column that must become variable names, or an API field that has to switch from snake_case to camelCase.
Title Case follows the usual headline rules, so short words like "of" and "the" stay lowercase, and acronyms such as NASA keep their capitals. Everything runs in your browser, so your text never leaves your device.
How to use it
- Add your textType or paste into the left box, or drop a text file onto it. Sample fills in two lines to try.
- Pick a caseClick one of the twelve buttons. The result appears on the right at once and updates as you keep typing.
- Adjust Title CaseTurn off "keep short words lowercase" to capitalize every word. Turn off "Keep acronyms and names" if you want words like NASA or iPhone changed too.
- Chain conversionsUse as input moves the result back into the left box, so you can apply another case on top of it.
- Copy the resultCopy puts the converted text on your clipboard, ready to paste.
Key features
Twelve cases
UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, aLtErNaTiNg and iNVERSE.
Headline-style Title Case
Articles, short conjunctions and short prepositions stay lowercase in the middle of a title. The first word, the last word and the word after a colon are always capitalized.
Acronyms and brand names kept
NASA, HTML, iPhone, iOS and JavaScript keep their capitals in Title Case and Sentence case.
Code-aware splitting
Programming cases split words at spaces, punctuation and capitals, so getHTTPResponseCode becomes get_http_response_code.
Line by line
Every line is converted on its own, so you can paste a whole list of names or headings at once.
Any alphabet
Accented, Greek and Cyrillic letters change case correctly, and German ß becomes SS in capitals.
Examples
Fixing a headline
Paste a title typed in lowercase:
harry potter and the prisoner of azkabanTitle Case gives Harry Potter and the Prisoner of Azkaban. With "keep short words lowercase" turned off, you get Harry Potter And The Prisoner Of Azkaban instead. A title typed in capitals, such as THE LORD OF THE RINGS, becomes The Lord of the Rings.
One name in every programming style
Here is "user profile ID" in each of the six programming cases:
| Case and result | Common use |
|---|---|
camelCaseuserProfileId | JavaScript variables, JSON keys |
PascalCaseUserProfileId | Class and component names |
snake_caseuser_profile_id | Python, database columns |
kebab-caseuser-profile-id | CSS classes, file names, URLs |
CONSTANT_CASEUSER_PROFILE_ID | Constants, environment variables |
dot.caseuser.profile.id | Config keys, translation keys |
Converting a list of field names
Paste three names written in three different styles, one per line:
first_name
last-name
EmailAddresscamelCase turns them into firstName, lastName and emailAddress. The tool finds the word boundaries in each style, so the input does not need to be consistent.
How tricky input is handled
| You type | Result |
|---|---|
| a guide to the best APIs for iOS developers | Title Case: A Guide to the Best APIs for iOS Developers |
| star wars: a new hope | Title Case: Star Wars: A New Hope |
| state-of-the-art design | Title Case: State-of-the-Art Design |
| version 2.0 release notes | kebab-case: version-2-0-release-notes |
| straße | UPPERCASE: STRASSE |
Tips
- Convert a whole column at once: copy it from a spreadsheet, paste it here and copy it back. Each cell is on its own line, and each line is converted separately.
- To switch an API payload from snake_case to camelCase, paste only the key names, one per line, rather than the whole JSON. Values and punctuation would be turned into words too.
- Read a Title Case result once before you publish it. Phrasal verbs such as "Log In" or "Pick Up" need a capital on the small word, and the tool cannot tell them apart from prepositions.
- Sentence case lowercases everything except the start of each sentence, acronyms and mixed-case names. Fix proper nouns such as city or people names by hand afterwards.
- For web addresses, use the Text to Slug tool instead of kebab-case. It also removes accents and characters that do not belong in a URL.
Common mistakes and limits
- Expecting Sentence case to know namesThe tool cannot tell that "Paris" or "Harry" is a name, so "my friend from Paris" becomes "My friend from paris". Acronyms and words with an inner capital, like iPhone, are the exception.
- Converting text with apostrophes into code casesApostrophes split words in programming cases, so "don't stop me now" becomes don_t_stop_me_now. Remove apostrophes first if that matters.
- Losing capitals in mixed-case wordsProgramming cases split at every capital, so iOS becomes i_os and APIs becomes ap_is. Fix those by hand or write them in lowercase before converting.
- Expecting UPPERCASE to be reversibleSome letters change length. German ß becomes SS in capitals, and converting back to lowercase gives "strasse", not "straße".
- Assuming one Title Case standardStyle guides disagree about prepositions. This tool capitalizes longer ones such as "over", "with" and "from", which some guides, such as Chicago style, keep lowercase.
