Free Case Converter
Nine cases, including proper Title Case that leaves the small words alone.
Retyping a heading in a different case is the kind of task that takes thirty seconds and interrupts a train of thought. This converter handles nine of them, including the two that most online converters get wrong: Title Case that keeps articles and short prepositions lowercase, and the programming cases that need to detect word boundaries in text that has none.
How it works
Paste your text
It stays in the box — nothing is sent anywhere.
Pick a case
Nine options, from plain lowercase to CONSTANT_CASE.
Copy or keep going
Copy the result, or move it back into the input to chain conversions.
Title case is not one rule but several
Most converters implement title case as "capitalise every word", which produces "The Rise Of The Machines" — recognisably wrong to anyone who edits for a living. The style guides agree that minor words stay lowercase; they disagree about which words are minor.
Chicago keeps articles, coordinating conjunctions and all prepositions lowercase regardless of length, so "Notes on the Making of a Film" keeps both "on" and "of" down. AP capitalises any word of four letters or more, which promotes "With", "Over" and "From". APA follows the four-letter rule too but capitalises everything after a colon. All three agree on one thing: the first and last word of a title are always capitalised, whatever they are.
This tool follows the Chicago convention and always capitalises the opening and closing word. If your house style is AP, the handful of four-letter prepositions are the only places you will need to intervene — which is a smaller edit than fixing every article by hand.
Why programmers argue about case at all
The programming cases are not decoration. Each one signals something to a reader: in most codebases PascalCase names a class or type, camelCase a variable or function, and CONSTANT_CASE a value that never changes. Seeing the case tells you what kind of thing you are looking at before you read the name.
The conventions split along language lines and rarely mix. Python and Rust use snake_case for functions and variables; Java, JavaScript and C# use camelCase; Go uses PascalCase for anything exported from a package, which makes capitalisation part of the language rather than a style preference. CSS classes and URL slugs use kebab-case, because a hyphen is legal there and an underscore is easy to lose under a text underline.
Converting between them means finding word boundaries in text that may not have any. This tool splits on spaces and punctuation, and also on the lowercase-to-uppercase transition — so getUserName becomes get_user_name rather than one long lowercase run. Acronyms remain the awkward case: parseHTTPResponse has no boundary a machine can see between the letters of the acronym.