Case Converter

What each button does

Paste your text in the top box and click a button. The result appears in the box below. Your original text stays in the top box, so you can try every button on the same text. The result does not update while you type. Click the button again after each change.

Here is the phrase the lord of the rings run through each button:

Title Case: simple rules, so check the result

This tool capitalizes the first letter of every word. A word is anything between spaces, line breaks or hyphens, so well-known becomes Well-Known. The tool does not follow a style guide such as AP or Chicago. Those guides keep short words such as a, of, the and and small in the middle of a title. So the tool gives The Lord Of The Rings, while the book title is written The Lord of the Rings. Fix those small words by hand.

A few more things to watch:

• Apostrophes. Only the first letter of a word gets a capital, so the letter after an apostrophe stays small. don't stop becomes Don't Stop, and my cat's toy becomes My Cat's Toy. The other side of this rule: o'brien becomes O'brien, so fix names like O'Brien by hand.
• Short forms in capitals. The text is made small first, so NASA and the FBI becomes Nasa And The Fbi. iPhone becomes Iphone and McDonald becomes Mcdonald.
• Accented letters and other alphabets work. café crème becomes Café Crème, émile zola becomes Émile Zola, and Russian привет мир becomes Привет Мир. If a word starts with a quote or a bracket, the first letter after it gets the capital: (hello) becomes (Hello).

Sentence case: good for fixing text typed in capitals

Sentence case puts a capital on the first letter of the text and on the first letter of every new line. It also puts one on the first letter after a . ! or ? that is followed by a space or a line break. Everything else becomes small. HELLO WORLD. HOW ARE YOU? becomes Hello world. How are you? Accented and non-English letters get a capital too: émile zola. éric too becomes Émile zola. Éric too. An opening quote or bracket is skipped, so "hello," she said becomes "Hello," she said.

The tool does not know names or the word I. yesterday i went to paris becomes Yesterday i went to paris. NASA becomes nasa. Read the result once and put the capitals back on names.

Two more rare cases:

• Every new line starts a sentence, even when the sentence goes on from the line above. first line and second line on two lines become First line and Second line. If your text is one long sentence broken over several lines, fix those capitals by hand.
• A short form with a dot counts as a sentence end. e.g. this is it becomes E.g. This is it.

camelCase, snake_case and kebab-case for code and links

These three styles join words without spaces, so they can be used as names in code, in file names and in web addresses. Which one you need depends on where the name goes:

• camelCase for variable and function names in JavaScript and Java, for example userFirstName.
• snake_case for variable and function names in Python, and for many database column names, for example user_first_name.
• kebab-case for CSS class names and page addresses (URL slugs). 10 Best Tips for Kathmandu! becomes 10-best-tips-for-kathmandu.

Your team or project may have its own rules, so follow those first.

How these buttons find the words

• They split at spaces, hyphens, underscores and other symbols, and at camelCase humps. A hump is a small letter (or a digit) followed by a capital. So userFirstName becomes user_first_name with snake_case, and parseHTTPResponse becomes parse_http_response.
• You can switch between all three styles. user-first-name becomes user_first_name with snake_case, user_first_name becomes user-first-name with kebab-case, and both become userFirstName with camelCase.
• Symbols and extra spaces are cleaned up. Punctuation is removed, there is never a separator at the start or end, and repeated separators become one. Tips - Part 2 becomes tips-part-2, tips---part-2 also becomes tips-part-2, and First Name! becomes firstName. Apostrophes are removed, so don't stop becomes dont_stop.
• Letters from every language are kept. café crème becomes café_crème, and नमस्ते संसार becomes नमस्ते_संसार. Many programming languages, file systems and web addresses work best with only a to z, so replace accented letters with plain ones if you need that.
• Letters and digits next to each other stay together. part2 stays one word, so version2Beta becomes version2_beta.

UPPER, lower and tOGGLE: a few surprises

• tOGGLE fixes Caps Lock mistakes. If you typed with Caps Lock on and got hELLO wORLD, tOGGLE turns it into Hello World.
• German ß. UPPER CASE turns straße into STRASSE, the standard capital form. lower case then gives strasse, not straße. Keep a copy of the original text.
• Turkish and other languages. The tool uses the standard rules built into your browser, not the rules of one language. So Turkish i becomes I, not the dotted İ. For Turkish text, check the result.
• Letters without case. Nepali, Hindi, Chinese and Japanese have no capital letters. UPPER, lower and Title Case leave that text as it is.