Convert Case

Text cases explained: sentence, title, camelCase and more

How to change a heading to title case and snake_case

Take the heading the quick brown fox jumps over the lazy dog.

1. Title Case capitalizes the first word and every word of four letters or more, and keeps the second "the" lowercase: The Quick Brown Fox Jumps Over the Lazy Dog
2. snake_case lowercases the words and joins them with underscores, ready for a variable or file name: the_quick_brown_fox_jumps_over_the_lazy_dog
3. Swap moves that result to the left pane. Choosing camelCase now splits it at the underscores and gives theQuickBrownFoxJumpsOverTheLazyDog

How camelCase and snake_case split words

camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE first split the text into words. A new word starts at any space or punctuation mark, at a lowercase letter followed by an uppercase one, and before the last capital of a run of capitals.

That is why parseHTTPResponse becomes parse_http_response and not parse_h_t_t_p_response. Each line is converted on its own, so a list of names stays a list.

What case conversion leaves unchanged

Sentence, lower, upper, capitalized, alternating and inverse case only touch letters. Digits, punctuation, line breaks and spacing stay exactly as you typed them. The five code cases remove punctuation and spaces, because that is their job.

The tool has no dictionary. Sentence case will lowercase names and acronyms ("paris", "nasa"), so check proper nouns after converting. Title Case keeps a word that you typed with capitals inside it, such as iPhone or NASA, unless the whole line is in capitals.

For a headline that has to follow APA, AP, Chicago or MLA style, use Capitalize My Title, which knows each guide's list of short words. For bold or italic letters that survive a copy and paste into a profile or a plain-text message, the Unicode text converter swaps letters for styled characters. After converting a list, the alphabetical order generator sorts it, and the letter counter checks its length.