Case Converter
Eight case styles with live conversion — no Apply button. Title Case comes with style presets and an editable minor-word list, and Sentence Case knows that a period after Dr. or e.g. is not a new sentence.
Your text
Keyboard: Ctrl+1…Ctrl+8 switches modes. Your first pasted text is kept as the "original" for the reset button.
Minor words stay lowercase unless they are the first or last word of a line. Edit the list to switch to a custom set.
Sentence Case capitalizes after . ! ?, at the start of each line, and promotes standalone i to I. Known abbreviations (Mr. Dr. e.g. U.S. and similar) do not start a new sentence.
Result
characters 0 · words 0 · lines 0 · bytes 0