Case Converter

What the case converter does

Text often arrives in the wrong case. A heading was typed with Caps Lock on, a spreadsheet export is all capitals, or a list of field labels needs to become variable names. Retyping is slow and invites typos. This tool rewrites the letters in place: paste the text, press the case you want, and copy or download the result. Undo steps back through your last 50 conversions, so you can try a few styles and keep the one that reads best.

The writing cases

• UPPER CASE turns every letter into a capital. Useful for short labels and signage, tiring to read in long passages.
• lower case removes every capital, handy before you clean up a messy import.
• Title Case capitalises the main words of a heading. Short articles, conjunctions and prepositions (a, an, the, and, but, or, of, in, on, at, to, by, for, via and a few more) stay small, except when they open or close the title or follow a colon. Words that already mix capitals, such as NASA or iPhone, are left as they are, unless the whole text was in capitals, in which case everything is rebuilt from scratch.
• Sentence case lowers everything and then capitalises the first letter of each sentence and the pronoun "I". Names inside a sentence are not detected, so check proper nouns afterwards.
• aLtErNaTiNg and iNVERSE are playful styles. Alternating flips every other letter and ignores digits and spaces; inverse swaps the case of each letter, so running it twice gives back the original.

The code naming styles

Programming languages and file systems prefer names without spaces. The tool first splits your text into words at spaces, punctuation, underscores, hyphens and at the point where a lower case letter meets a capital, so "userFirstName", "user first name" and "user_first-name" all give the same three words. Apostrophes are dropped. It then joins them again:

• camelCase for JavaScript and Java variables: userFirstName
• PascalCase for class and component names: UserFirstName
• snake_case for Python, Ruby and database columns: user_first_name
• kebab-case for URLs, CSS classes and file names: user-first-name
• CONSTANT_CASE for constants and environment variables: USER_FIRST_NAME

Runs of capitals are treated as one acronym, so "XMLHttpRequest" becomes xml_http_request in snake_case. Each line is converted on its own, which means you can paste a column of fifty labels and get fifty variable names back.

A worked example

Paste the line "monthly EMI amount for home loan". Title Case gives "Monthly EMI Amount for Home Loan": "for" stays small, and "EMI" keeps its capitals. camelCase gives monthlyEmiAmountForHomeLoan, and CONSTANT_CASE gives MONTHLY_EMI_AMOUNT_FOR_HOME_LOAN.

Other languages

Capitals exist in Latin, Greek, Cyrillic and Armenian scripts, and the tool uses your browser's Unicode rules for them, so "straße" becomes "STRASSE" and accented letters keep their accents. Hindi, Tamil, Arabic and Chinese have no upper or lower case; their letters pass through unchanged, and the code styles simply join their words with an underscore or a hyphen.

Privacy and limits

The conversion runs on your device and nothing is sent to Ur Next Door. Style guides disagree about which words to keep small in a title, so a publisher with a house style may still want a final read. Brand names that are normally written in lower case lose that styling in Title and Sentence case.