Skip to content

Case converter

Change text between UPPERCASE, lowercase, Title Case, camelCase and more, instantly in your browser.

in Title Case

Nothing is uploaded. The conversion runs on your device.

How it works

Paste or type your text into the box, then choose a case beside it. The result appears right under your text and changes as you type or pick another case, because the whole transform happens on your device. When it looks right, copy it with one click.

Nothing you enter is sent to a server. The tool has no account, no upload and no history, so it is safe to use with drafts, names and other text you would rather keep private.

What each case means

Every case below is shown with the same phrase, the quick brown fox, so you can compare them at a glance.

UPPERCASE
Every letter capitalised. Good for headings you want to shout or for acronyms. “THE QUICK BROWN FOX”
lowercase
Every letter in lower case, spacing and punctuation untouched. “the quick brown fox”
Title Case
Each major word capitalised; short words like “a”, “of” and “the” stay lower case unless they are first or last. See the exact rule below. “The Quick Brown Fox”
Sentence case
Lower case throughout, with the first letter of each sentence capitalised. It does not restore proper nouns. “The quick brown fox”
camelCase
First word lower case, every later word capitalised, joined with no spaces. Common for variables and functions in JavaScript and Java. theQuickBrownFox
PascalCase
Like camelCase but the first word is capitalised too. Common for class and type names. TheQuickBrownFox
snake_case
Lower-case words joined by underscores. Common in Python, Rust and database columns. the_quick_brown_fox
kebab-case
Lower-case words joined by hyphens. Common in URLs, CSS class names and file names. the-quick-brown-fox
CONSTANT_CASE
Upper-case words joined by underscores. Common for constants and environment variables. THE_QUICK_BROWN_FOX
aLtErNaTiNg case
Letters alternate between lower and upper case, starting with lower. The “mocking SpongeBob” look for memes. “tHe qUiCk bRoWn fOx”
toggle case
Swaps the case of every letter: lower becomes upper and upper becomes lower. ““Hello World” becomes “hELLO wORLD””

How Title Case decides what to capitalise

Title Case here is a simple, rule-based transform. It is not AP, APA, Chicago or any other named editorial style; it does not know parts of speech, proper nouns or hyphenated-compound rules. If you need a specific house style, treat the result as a starting point and adjust by hand.

The exact rule it follows is:

  • A “word” is a run of letters, digits and apostrophes. Everything else (spaces, hyphens, underscores, slashes and other punctuation) separates words and is kept exactly as you typed it. So mother-in-law becomes Mother-In-Law, not Mother In Law.
  • A word that looks like code is split into its words first, the same way the code cases split them. It looks like code when it has two or more capital-letter humps, a letter next to a digit, or an underscore joining it to the next word, so getUserName becomes Get User Name. Capitals that form an acronym inside such a word are kept, so XMLHttpRequest becomes XML Http Request. Sentence case splits words the same way.
  • A word with a single hump, the way brand names are written, stays whole and keeps its capitals exactly: iPhone, eBay, McDonald, YouTube and JavaScript come out as you typed them.
  • Each word is lower-cased, then its first letter is capitalised.
  • Interior short words stay fully lower case. The first word of every sentence and the last word are always capitalised, even when they are short words, so stop here. the end becomes Stop Here. The End and the lord of the rings becomes The Lord of the Rings.

The short words kept lower case are this fixed list: a, an, and, as, at, but, by, for, if, in, nor, of, off, on, or, per, so, the, to, up, via, vs, yet. Matching is case-insensitive and it looks at whole words only. A word typed entirely in capitals, such as NASA, has no camelCase hump, so it is cased like any other word.

Developer cases, and when to use them

The identifier cases first break your text into words (on spaces, punctuation and existing case boundaries), then rejoin them a different way. That means you can paste an identifier in one style and get it back in another: getUserName converts cleanly to get_user_name.

  • camelCase and PascalCase: variables, functions and types in languages like JavaScript, TypeScript, Java and C#.
  • snake_case: Python and Rust identifiers, and SQL column names.
  • kebab-case: URL slugs, CSS class names, and file names on the web.
  • CONSTANT_CASE: fixed constants and environment variables, like MAX_RETRIES.

Private by design

The conversion runs entirely in your browser using plain JavaScript. Your text is never uploaded, logged or stored, so once the page has loaded you can keep converting without a network connection and without worrying about where the text goes.

Need to count instead of convert? Try the word & character counter.

Related tools

Common questions

Is the case converter free and private?
Yes. It is free, needs no account, and runs entirely in your browser. The text you enter is never uploaded.
How do I change text to all capitals?
Paste your text into the box and pick UPPERCASE. The all-caps version appears under your text straight away, ready to copy.
What is the difference between Title Case and Sentence case?
Title Case capitalises each major word (keeping short words like “of” and “the” lower case). Sentence case capitalises only the first letter of each sentence and leaves the rest lower case. Both split code-style words such as getUserName into separate words, and leave brand names such as iPhone or YouTube as you typed them.
Which words stay lower case in Title Case?
A fixed list of short articles, conjunctions and prepositions: a, an, and, as, at, but, by, for, if, in, nor, of, off, on, or, per, so, the, to, up, via, vs, yet. The first word of each sentence and the last word are always capitalised, even if they are on that list.
Does it follow AP or APA title-case rules?
No. Title Case here is a simple capitalise-the-major-words rule, not AP, APA or Chicago style. Use it as a quick starting point and fine-tune to a specific style guide if you need one.
What is camelCase?
The first word is lower case and each following word is capitalised with no spaces, like firstName. It is common for variables and functions.
What is snake_case?
Words joined by underscores, usually lower case, like first_name. Common in Python, Rust and database columns.
What is kebab-case?
Words joined by hyphens, lower case, like first-name. Common in URLs, CSS class names and file names.
What is CONSTANT_CASE?
Upper-case words joined by underscores, like MAX_SIZE. Common for constants and environment variables.
Can I convert back to the original capitalisation?
Conversion is one-way: it does not remember the original mix of cases. Keep a copy of the source, or paste it again, if you need the original back.
Does it work with accented and non-English letters?
Yes. It uses locale-aware casing, so standard Unicode text (accented Latin letters and other scripts) is handled correctly.
Does it need an internet connection?
Only to load the page the first time. The conversion itself runs on your device, so it keeps working while the page is open even if you go offline.