Case converter

Every version at once, rather than picking first

Most converters make you choose a case, press a button, and look at the answer. Then you realise you wanted a different one and do it again.

This shows all twelve as you type. It is quicker, and it is genuinely useful for the cases most people cannot name, because seeing "The Lord of the Rings" next to "The Lord Of The Rings" settles which one you meant faster than knowing that one is called title case.

Title case is not capitalising every word

This is the one nearly every online converter gets wrong, and it is the reason most of them are not much use for anything you would actually publish.

Proper title case leaves short joining words lowercase unless they come first or last."The Lord of the Rings", not "The Lord Of The Rings". Articles, short prepositions and conjunctions all stay down: a, an, the, and, but, or, of, in, on, to, for, with.

A converter that just capitalises everything and calls it title case is really a capitalise-every-word tool with the wrong label. Both are here, named honestly, so you can pick the one you want.

Acronyms survive

Any word with a capital letter after its first is left exactly as it is. So NHS stays NHS, PDF stays PDF, and McDonald stays McDonald, rather than being flattened into Nhs, Pdf and Mcdonald the way a naive converter does it.

Sentence case has to find the sentences

Fixing a paragraph typed with caps lock on is the other common job, and it is harder than it looks because you cannot just capitalise after every full stop.

Do that and "Mr. Smith arrived" becomes two sentences, and "use a claw hammer, e.g. this one" becomes three. The common abbreviations are stepped over here: Mr, Mrs, Dr, Prof, St, No, vs, etc, e.g., i.e. and the rest.

The standalone pronoun I is also put back, because lowercasing everything eats it and no other tool seems to notice.

The programming conventions

All of these mean the same words joined a different way, and which one you need depends entirely on where it is going:

• camelCase for variables and functions in JavaScript, Java and Swift.
• PascalCase for classes and components.
• snake_case for Python, Ruby and almost every database column name.
• kebab-case for CSS classes, HTML attributes and file names.
• CONSTANT_CASE for constants and environment variables.

The splitting handles all of them going in as well as coming out, so you can paste parseHTML5File and get parse-html5-file rather than parse-h-t-m-l5-file. A run of capitals followed by a normal word is treated as one word, which is what makes HTMLParser come out as two rather than five.

The URL slug does a bit more

As well as hyphenating, it strips accents down to their base letters and removes punctuation entirely. Café Ratón becomes cafe-raton, not caf-ratn, which is what you get from a converter that deletes anything non-ASCII rather than decomposing it first.