How to use the Case Converter
- Type or paste the words or sentences you want to convert into the input box.
- All 10 results, including UPPERCASE, lowercase and Title Case, appear below as you type.
- Click the Copy button next to the result you need and paste it wherever you like.
When you need to change uppercase and lowercase
- Fixing text you typed with Caps Lock on, without retyping it
- Making headings and names consistent with capitalized first letters (for example essay titles, report headings or slide decks)
- Converting email addresses or usernames from a spreadsheet to all lowercase so duplicates are easy to spot
- Switching variable names or file names between naming conventions when programming
Title Case vs. Sentence case
Title Case is used for headlines and titles: the first letter of each major word is capitalized. Articles (a, an, the), short prepositions (of, in, on and so on) and conjunctions (and, or) stay lowercase unless they start the title. This tool follows that convention.
Sentence case capitalizes only the first letter of the sentence, as in normal writing. Proper nouns (London, Google and so on) are also lowercased, so fix those by hand after converting.
| Style | Example |
|---|---|
| Title Case | The Lord of the Rings |
| Sentence case | The lord of the rings |
Many websites, news outlets and UK publications prefer Sentence case for headings, while US book and film titles usually use Title Case. Pick the one that matches your style guide.
camelCase, snake_case and kebab-case explained
| Style | Example | Commonly used for |
|---|---|---|
| camelCase | userName | JavaScript and Java variables and functions |
| PascalCase | UserName | Classes, React components |
| snake_case | user_name | Python variables, database columns |
| kebab-case | user-name | URLs, CSS classes, file names |
| CONSTANT_CASE | USER_NAME | Constants, environment variables |
Whatever style your input is in, the tool detects the word boundaries and rebuilds the name. For example, getUserIDFromAPI becomes get_user_id_from_api in snake_case.
Are email addresses and usernames case-sensitive?
The domain part of an email address (after the @) is not case-sensitive. The part before the @ technically can be under the standard, but Gmail, Outlook, Yahoo and most other email providers ignore case and treat both versions as the same address. Converting a mailing list to all lowercase makes duplicates much easier to find.
Passwords, on the other hand, are almost always case-sensitive. If you can't log in, check whether Caps Lock is on first.
Other ways to change case
- Excel and Google Sheets: use
=UPPER(A1),=LOWER(A1)or=PROPER(A1). - Microsoft Word: select text and press
Shift+F3to cycle through cases.
These built-in options don't offer Sentence case with proper title rules or programming styles like camelCase and snake_case, which is where this tool helps.