Case Converter

In short A case converter rewrites the capitalisation of text without touching the words, and the twelve cases it offers exist for different reasons. UPPER and lower are formatting. Title Case and Sentence case are editorial conventions with style-guide rules behind them. The programming cases — camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE — are naming conventions, and which one is correct depends entirely on the language: JavaScript uses camelCase for variables and PascalCase for classes, Python uses snake_case, CSS and URLs use kebab-case, and environment variables are CONSTANT_CASE almost everywhere. The conversions that lose information are worth knowing about. Going to lowercase and back cannot restore proper nouns, because nothing in the text records that "Paris" was a city rather than plaster. Converting to snake_case discards the original word boundaries if they were only marked by capitals, so PascalCase to snake_case works and the reverse relies on guessing. That is why the sensible order is to convert from the most informative form you have, not through an intermediate one.