Uppercase and lowercase converter
Paste your text and transform it with one click: all uppercase, all lowercase, sentence case, title case or inverted. It respects accents, and nothing is sent to any server.
What each mode is for
Converting text from one form to another saves the tedious work of retyping. The most common modes are four: UPPERCASE to stand out or to fill in forms that demand it; lowercase to fix text typed by accident with caps lock on; Title Case, with the first letter of each word capitalised; and Sentence case, which capitalises only the first letter of each sentence, as in ordinary text.
Title case in English: which words to capitalise
English title case has a subtlety many people miss. You don't capitalise every word: the major ones (nouns, verbs, adjectives) yes, but short articles, conjunctions and prepositions such as "a", "the", "and", "of" or "in" stay lowercase, unless they're the first or last word. So it's "The Lord of the Rings", not "The Lord Of The Rings". A plain title case that capitalises everything is quick, but it isn't strictly correct for a polished heading, so it's worth knowing the difference.
Rescuing text "burned" by caps lock
The most satisfying use is rescuing a paragraph you typed entirely in capitals without noticing. Rather than deleting it and starting over, you paste it, switch it to lowercase or sentence case, and it's ready in a second. It's also handy for tidying up data: names, lists or columns that arrive in different formats and you want to make uniform.
For developers too
Beyond the everyday modes, formats like camelCase and snake_case are part of daily life in programming, where variable and file names follow strict conventions. Whatever the mode, the text is processed in your browser, so you can paste any content without it leaving your device.