Free Case Converter

Type or paste text into the box, then pick a case. The case converter rewrites the text in place, keeps your cursor and selection where they were, and adds the change to one undo history together with your typing. Press Control and Z (Command and Z on a Mac) to step back, and add Shift to step forward again; the Undo and Redo buttons do the same on a phone.

• Sentence case: lowercase, with a capital at the start of each sentence and each line, and the pronoun I capitalized.
• lower case and UPPER CASE: every letter in one case, using your browser's language rules, so ß becomes SS in capitals and accented letters keep their accents.
• Title Case in four styles: AP, Chicago, APA and MLA, each with its own list of small words.
• Code cases: camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE, plus a URL slug.

Title case and the code cases treat each line on its own, so a list of headings or variable names converts in one go and the line breaks stay where they were.

Title case capitalizes the main words of a title and leaves short words such as a, the, and and of in lowercase. The styles agree on the big picture and on the first word, which is always capitalized, but they disagree on which short words stay lowercase. Use the style your publication, school or client asks for; if nobody asks, pick one and use it everywhere.

AP suits news and marketing sites, and it is the style most blogs follow. Chicago is common in books and long-form publishing. APA is for psychology, education and other social science papers, and MLA for the humanities. The tool lists the source of each rule and the date it was checked under Title case rules and sources.

The clearest test is a word of four or more letters that is a preposition, such as with, from or into. AP and APA capitalize every word of four letters or more, so they write Gone With the Wind. Chicago lowercases prepositions of four letters or fewer and capitalizes longer ones, so it writes A Room with a View but All About Eve. MLA lowercases prepositions of any length, so it writes A Walk through the Woods between Seasons.

• Last word: AP, Chicago and MLA always capitalize it (What It Is For). APA states no last-word rule, so a short minor word at the end stays lowercase (What It Is for).
• Subtitles: Chicago, APA and MLA capitalize the first word after a colon. AP's entry for titles does not mention subtitles, so a short word after a colon stays lowercase in AP style; capitalize it by hand if your house style does.
• Hyphenated words: the first part is always capitalized. Chicago, APA and MLA keep a small word inside a compound in lowercase (Up-to-Date, Self-Report). AP states no rule for hyphens, so the converter capitalizes every part (Up-To-Date).
• Yet and so: MLA lowercases them as coordinating conjunctions; Chicago lowercases only and, but, for, or and nor.

A word's case often depends on what it does in the sentence, and the converter reads words, not grammar. Up is a preposition in Up the Hill but part of a verb in Sign Up, where every style capitalizes it. The converter lowercases it in both, so check phrasal verbs such as Log In, Set Up and Look Up by hand.

For the same reason, words that are as often a verb, adjective or conjunction as a preposition (like, near, past, since, until, after, before and than) are always capitalized, since lowercasing Like in I Like Mondays would be wrong. Names and acronyms are safe in mixed-case text: a word with a capital after its first letter, such as SEO or iPhone, is kept as you typed it. A title typed all in capitals is lowercased first, so brand names in it need a second look.

Sentence case capitalizes only the first word and proper nouns, the way a normal sentence does. Many style guides and product teams prefer it for web headings, buttons and email subject lines, because it reads faster and avoids arguments about small words. Google's own developer documentation style guide uses sentence case for headings, and AP uses it for news headlines.

The sentence case button lowercases everything and then capitalizes the first letter of each sentence and each line. It cannot tell which words are names, so put the capitals back on names, places and brands after converting, or convert a copy and fix it once.

Code cases join the words of a phrase into one name that has no spaces. The converter splits your text into words at spaces, punctuation and existing case changes, so parseXMLHttpRequest, parse-xml-http-request and Parse XML HTTP request all give the same words.

• camelCase: first word lowercase, later words capitalized (maxRetryCount). Common for JavaScript and Java variables.
• PascalCase: every word capitalized (MaxRetryCount). Common for class and component names.
• snake_case: lowercase words joined by underscores (max_retry_count). Common in Python and database columns.
• kebab-case: lowercase words joined by hyphens (max-retry-count). Common in CSS classes and file names.
• CONSTANT_CASE: uppercase words joined by underscores (MAX_RETRY_COUNT). Common for constants and environment variables.

Apostrophes are dropped inside a word, so don't becomes dont, and accented letters are kept. For a web address, the slug button also spells accented letters in plain ASCII; the URL slug generator adds a length target, stop-word removal and many titles at once.