Case Converter
UPPER, lower, Title, camelCase, snake_case and more. Runs in your browser.
About this case converter
This case converter changes the capitalization of any text in one click. Fix a paragraph typed with Caps Lock on, turn a heading into proper Title Case, or rename a list of variables to camelCase, snake_case or kebab-case. The result updates as you type, so you can paste, pick a case and copy.
It covers both writing and code. Writers and editors get Sentence case, lower case, UPPER CASE, Title Case and Capitalized Case. Developers get camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and dot.case, with each line treated as one name so you can convert a whole list at once.
Title and Sentence case keep acronyms and brand names such as NASA and iPhone as you typed them, a step many converters skip. Everything runs in your browser, and your text is never uploaded.
Features
Proper Title Case
Short articles, conjunctions and prepositions such as a, an, the, and, of, in and on stay lowercase unless they are the first or last word or follow a colon. Each part of a hyphenated word is capitalized.
Sentence case that reads naturally
The first letter of each sentence and each line is capitalized, the pronoun I is fixed (including I'm and I've), and numbers such as 3.5 do not start a new sentence.
Keeps acronyms and brand names
Words with a capital after the first letter, such as NASA, iPhone or McDonald, stay as typed. If the whole text is in capitals, it is treated as shouting and fully converted.
Six code cases
camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and dot.case. Acronyms split correctly, so XMLHttpRequest becomes xml_http_request.
Converts lists line by line
In code cases each line becomes its own name, so a column of field names pasted from a spreadsheet stays a column.
Works with any alphabet
Accented letters, German ß, Greek and Cyrillic convert correctly. Emoji and scripts without capital letters are left as they are.
Copy, download or keep editing
Copy the result, download it as a .txt file, or press Use as input to apply another case on top.
How to use the case converter
- 1Paste your text.
- 2Click the case you want.
- 3Copy the converted text.
When to use it
Fixing Caps Lock text
Turn a paragraph typed in all capitals into normal Sentence case without retyping it.
Headlines and titles
Format blog titles, email subject lines, slide headings and book or song titles in Title Case.
Renaming variables and fields
Convert column names to snake_case for a database, or API fields to camelCase for JavaScript.
Creating URL slugs and CSS classes
Turn a page title into kebab-case for a URL slug or a CSS class name.
Constants and environment variables
Turn a setting name into CONSTANT_CASE, such as MAX_UPLOAD_SIZE, for config files and code.
camelCase vs snake_case vs kebab-case: where each is used
Code cases join several words into one name without spaces. Each language and tool has its own convention, and following it makes code easier to read.
- camelCase (userName): variables and functions in JavaScript, TypeScript and Java, and keys in most JSON APIs.
- PascalCase (UserName): classes, types and React components in most languages, and public members in C#.
- snake_case (user_name): variables and functions in Python and Ruby, and table and column names in SQL databases.
- kebab-case (user-name): URL slugs, CSS class names, HTML attributes and file names.
- CONSTANT_CASE (USER_NAME): constants and environment variables in almost every language.
- dot.case (user.name): configuration keys and translation keys in some frameworks.
Title Case rules
Title Case capitalizes the main words of a title. Style guides differ on the details, but most agree on the basics, and this tool follows them in the AP and APA style: capitalize the first and last word, capitalize nouns, verbs, adjectives and adverbs, and keep short articles, conjunctions and prepositions in lowercase.
The lowercase words here are a, an, the, and, but, or, nor, for, so, yet, as, at, by, in, of, off, on, per, to, up, via and vs. Longer prepositions such as with, from and about are capitalized. A word right after a colon is always capitalized, so "Mavros: a guide" becomes "Mavros: A Guide".
Chicago style lowercases all prepositions regardless of length. If you follow Chicago, check words such as With, From and Into after converting.
Sentence case vs Title Case vs Capitalized Case
Sentence case capitalizes only the first word and proper nouns, like a normal sentence. Many websites, apps and news sites now use it for headings because it reads more naturally.
Title Case capitalizes major words and leaves small words lowercase. It is the classic style for book, film and article titles.
Capitalized Case capitalizes every word, including small ones such as "of" and "the". It suits names, labels and short button text, but not formal titles.
Why use Mavros
| Mavros | Typical upload sites | |
|---|---|---|
| Where your text goes | Stays in your browser | Often sent to a server |
| Text and code cases | Both on one page | Usually one or the other |
| Acronyms in Title Case | NASA and iPhone kept | Often become Nasa and Iphone |
| Small words in titles | Kept lowercase by rule | Often every word capitalized |
| Lists of names | Converted line by line | Joined into one long name |
Tips
- Sentence case cannot know every proper noun. Check names of people, places and products after converting.
- Turn off Keep acronyms if your text has shouted words in capitals that you want lowercased.
- Paste one name per line to convert a whole list of variables or columns at once.
- Use Use as input to chain conversions, for example lower case first, then Title Case.
- For URL slugs, kebab-case drops punctuation for you, but check that the result is short and readable.
Questions
How do I change text from uppercase to lowercase?
Paste your text and click lower case. To get normal sentences instead of all lowercase, click Sentence case.
Which words stay lowercase in Title Case?
Short articles, conjunctions and prepositions (a, an, the, and, of, in, on…) stay lowercase unless they are the first or last word.
What is the difference between Title Case and Capitalized Case?
Title Case leaves small words such as "of" and "the" in lowercase. Capitalized Case capitalizes the first letter of every word.
What is camelCase?
camelCase joins words without spaces and capitalizes each word after the first, as in firstName. It is the usual style for variables in JavaScript and Java.
What is the difference between camelCase and PascalCase?
Both join words with capitals, but PascalCase also capitalizes the first word: firstName is camelCase and FirstName is PascalCase.
When should I use snake_case or kebab-case?
Use snake_case for Python code and database columns. Use kebab-case for URLs, CSS classes and file names.
Will it change acronyms like NASA?
Not in Title, Capitalized or Sentence case while Keep acronyms is on. Words with a capital after the first letter stay as typed. UPPER, lower and the code cases always convert every letter.
Does it work with accented letters and other languages?
Yes. It handles accented letters and alphabets such as Greek and Cyrillic. Scripts without capital letters, such as Chinese or Arabic, are left unchanged.
Is my text uploaded?
No. Conversion runs in your browser and nothing you paste is sent or stored.