Convert text between different cases instantly
QRSwift's Case Converter transforms any block of text into six different letter-case formats in a single click. It's useful for writers fixing inconsistent capitalisation, developers converting variable names between coding conventions like camelCase and snake_case, and anyone who needs to reformat copy quickly without manually retyping. Paste in as much text as you like — the conversion is instant and runs entirely in your browser with no data ever leaving your device.
Paste your text
Type or paste any text into the input box — a single word, a sentence, or multiple paragraphs all work fine.
Pick a case format
Click any of the six buttons — UPPERCASE, lowercase, Title Case, snake_case, camelCase, or iNVERSE — to apply that transformation.
Review the result
The converted text appears immediately in the output box below. Try different formats as many times as you like — the input is never altered.
Copy and move on
Hit Copy Output to send the result to your clipboard, or Clear All to reset both panels.
Both are conventions for writing multi-word identifiers without spaces, commonly used in programming. camelCase joins words by capitalising the first letter of each subsequent word, with no separator — e.g. myVariableName. It's standard in JavaScript, Java, and Swift. snake_case uses underscores as separators and keeps everything lowercase — e.g. my_variable_name. It's the norm in Python, Ruby, and SQL. Use this tool to switch between them instantly when copying code patterns or renaming variables.
Title Case capitalises the first letter of every word — The Quick Brown Fox. It's used for headings, book titles, and article headlines. Sentence case only capitalises the first word of each sentence (and proper nouns), like normal prose. This tool's Title Case button capitalises every word; if you need true sentence case, use the Lowercase button first, then manually capitalise proper nouns as needed.
Yes — there's no character limit imposed by the tool itself. You can paste entire articles, code files, or long documents and the conversion runs instantly on the whole input. The only practical ceiling is your browser's memory, which for typical text is essentially unlimited. For snake_case and camelCase conversions on multi-line content, note that line breaks are preserved and each line is treated as a separate phrase.