Free tool
Paste text on the left, click a case style, get the converted result on the right — instantly, entirely in your browser. Nothing is uploaded anywhere. Built by Imran Anwar, Principal Workday Integration Consultant, as a developer-focused take on the classic case-conversion tool: the usual prose cases (Sentence, lower, UPPER, Title, aLtErNaTiNg, InVeRsE) plus the programming identifier cases (camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE) that come up constantly when renaming variables, fields, or config keys.
Word-boundary detection. The programming-identifier conversions (camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE) tokenize your text on every boundary they can detect: whitespace, hyphens, underscores, and camelCase “humps” (a lowercase-to-uppercase transition, or a run of capitals followed by a capital+lowercase, so XMLHttpRequest splits into XML / Http / Request). That means converting between any of these five round-trips reasonably — paste userAccountID, get user_account_id, convert that to PascalCase, get UserAccountId, and so on. Punctuation outside of hyphens/underscores is treated as a boundary too and dropped from the output, so a full sentence converted to snake_case becomes a clean chain of lowercase words.
Sentence Case and Title Case use a simple heuristic (capitalize after start-of-text or after . / ! / ? for Sentence case; capitalize every word for Title Case) rather than a full grammar-aware capitalization ruleset — there's no exception list for articles/prepositions in Title Case, and Sentence case won't special-case abbreviations like “Dr.” or decimal numbers. Good enough for everyday text; not a proofreading tool.