Change case
Three formats for typesetting plus four for coding — all convertible in one place.
It first splits on underscores, hyphens, spaces, and camelCase boundaries, then rejoins in the target format — so helloWorld_test-name is also handled correctly.
When to use it
- Field names exported from a database arrive in mixed styles — user_first_name, UserFirstName, user-first-name — and you need them all as camelCase for the frontend or kebab-case for URLs.
- A whole column of English headings pasted from Excel or an old CMS is in ALL CAPS and you want title case before pasting it back.
When not to
- You are editing code: selecting the whole block rewrites string literals too, because the page has no parser to tell a variable from a quoted message.
- You need language-specific rules such as German ß→SS or Turkish i/İ: this page uses JavaScript's default case mapping, which ignores locale.
Conversion happens locally in your browser — nothing is uploaded and nothing reaches the URL or a log. Limits: plain text only and no syntax awareness, so string literals in code are rewritten too; the naming modes lowercase first, so all-caps acronyms do not survive; the page rewrites the whole text, so copy the original first.
Frequently asked
Does it touch Chinese characters or punctuation?
No. Chinese has no case, so upper and lower return the characters unchanged, and punctuation and digits are left alone. Only the three programming modes rearrange words, splitting on spaces, underscores and hyphens; other punctuation stays inside a word, so v1.2.3 is kept whole. Title case splits on whitespace only.
Why are ‘the’ and ‘of’ capitalised in title case?
Title case uppercases the first letter and lowercases the rest of every whitespace-separated word, with no idea of parts of speech. English headline conventions (short articles and prepositions in lowercase) need a manual pass afterwards; likewise iPhone becomes Iphone and eBay becomes Ebay, so check brand names after converting.
Why does an all-caps acronym come out lowercase in camelCase?
All three naming modes lowercase the whole input before splitting and rebuilding, so HTTP_SERVER_NAME becomes httpServerName rather than HTTPServerName. Restore the acronym by hand after converting; the same lowercasing is what keeps messy input such as UserNAME from producing odd capitals.