case converter
All seven cases at once, so you can see which one fits.
The short answer
Seven cases, all shown at once, because the reason people look this up is not knowing which one the thing they are pasting into wants. Title case is the only one with a judgement in it: the short words stay lowercase unless they land first or last, which is the rule most style guides settle on.
Sentence, title, upper, lower, camelCase, kebab-case and snake_case, each with a copy button. No dropdown, because the usual problem is not knowing which case the thing you are pasting into wants.
The formula
split on spaces, punctuation and camelCase boundaries, then rejoin under each case's own rule
Worked examples
- Title case
- Order Id 42 Sent
- camelCase
- orderId42Sent
- kebab-case
- order-id-42-sent
Reference table
| Case | Result | Where it is used |
|---|---|---|
| Sentence case | A tale of two cities | Prose, and anything you have to read |
| Title case | A Tale of Two Cities | Headlines, book and film titles |
| UPPER CASE | A TALE OF TWO CITIES | Shouting, and some legal headings |
| lower case | a tale of two cities | Usernames, tags, email addresses |
| camelCase | aTaleOfTwoCities | Variables in JavaScript and Java |
| kebab-case | a-tale-of-two-cities | URLs, CSS classes, filenames |
| snake_case | a_tale_of_two_cities | Databases, Python, environment variables |
How to use it
- 01Paste your textOne box. It splits on spaces, punctuation and camelCase boundaries alike, so it copes with text that is already in some other case.
- 02Copy the one you needEvery row has its own copy button. Nothing is sent anywhere; the conversion happens in the page.
Also searched for
Searches that land here include case converter, title case converter, uppercase to lowercase, camel case converter and snake case converter.
Seven cases and where each belongs
The three that are about prose
Sentence case is for anything anyone has to read: it is easier on the eye than title case and harder to get wrong. Title case is for headlines and the names of things. Upper case is for shouting, short labels and the occasional legal heading, and it costs about ten per cent more horizontal space than the same words in lower case, which is why it breaks layouts.
The four that are about machines
camelCase, kebab-case and snake_case exist because most languages and file systems will not accept a space. Which one to use is not a matter of taste but of where the string is going: JavaScript variables are camelCase, CSS classes and URLs are kebab-case, database columns and Python are snake_case. Getting it wrong usually produces something that works but looks foreign to everyone else in the codebase.
Why converting back is not always clean
Case conversion throws information away. Once "Order ID 42" has become order_id_42, nothing knows that ID was an acronym or that 42 was a separate word, so converting back gives "Order Id 42". Where the original casing matters, keep the original.
Questions people ask
Which words stay lowercase in title case?
Short function words: a, an, and, as, at, but, by, for, in, nor, of, on, or, the, to, up and via. They are capitalised anyway if they land first or last, which is why “What Are You Waiting For” keeps its final word capitalised. Style guides differ at the edges, mostly over prepositions of four letters or more.
What is the difference between camelCase and PascalCase?
Only the first letter. camelCase starts lowercase and is the convention for variables and functions in JavaScript and Java; PascalCase capitalises the first word too and is used for class and component names. Both strip the spaces.
Why does it break up acronyms?
Because leaving them joined produces the wrong result more often than not. “someHTTPValue” becomes some-http-value rather than some-httpvalue, which is what a URL or a CSS class needs. If you want an acronym kept whole, put a space in it before pasting.