Case Converter
Case converter: convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case and more. Free, no sign-up, and it runs in your browser.
Dedicated page: /en/case-converter
Quick answer
A case converter changes the capitalisation of any text in one click: UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case and more. Paste your text, pick a style, and copy the converted result for headlines, code, file names and social posts.
About this Case Converter
Case converter: convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case and more. It is one of the Text Tools on ToolUstad, and like every tool here it runs entirely in your browser: nothing you type, paste or open is uploaded to a server, and there is no sign-up or usage limit.
What is a case converter?
A case converter rewrites text in a different capitalisation style without changing the words themselves. It fixes the classic accidents, like typing a paragraph with Caps Lock on, and it applies the naming conventions that programming and publishing demand, where doing it by hand across hundreds of words is slow and error prone.
The case styles, explained
| Style | Example | Used for |
|---|---|---|
| UPPERCASE | THE QUICK BROWN FOX | Headlines, warnings, acronyms |
| lowercase | the quick brown fox | URLs, hashtags, normalising data |
| Title Case | The Quick Brown Fox | Book titles, headlines, headings |
| Sentence case | The quick brown fox | Normal sentences, UI labels |
| camelCase | theQuickBrownFox | JavaScript and Java variables |
| PascalCase | TheQuickBrownFox | Class names in most languages |
| snake_case | the_quick_brown_fox | Python, databases, file names |
| kebab-case | the-quick-brown-fox | URL slugs, CSS class names |
| CONSTANT_CASE | THE_QUICK_BROWN_FOX | Constants and environment variables |
When and why to convert case
- Fixing accidents: a page typed in all caps becomes readable sentence case in one click.
- Programming: turn a column of database names into camelCase variables, or labels into CONSTANT_CASE.
- Publishing: apply a consistent headline style across a whole article or table of contents.
- Data cleaning: normalise names and addresses pasted from spreadsheets in mixed case.
Best practices
- Convert a copy, not your only original, until you are sure the style is right.
- Check proper nouns after Title Case: it capitalises small words some style guides keep lowercase.
- For code, convert the whole list at once so naming stays consistent.
Common mistakes to avoid
- Using UPPERCASE for whole paragraphs online: it reads as shouting and hurts readability.
- Mixing snake_case and camelCase in the same codebase or spreadsheet.
- Retyping text by hand to change case, which introduces fresh typos.
Who is the case converter for?
Writers fixing drafts, developers renaming variables and constants, data entry staff cleaning lists, students formatting titles, and social media managers styling captions. Doing the same job with find and replace or manual retyping takes minutes per page and still misses words, while the converter applies one rule to the whole text instantly.
How the converter handles tricky text
Real text is messier than examples. This converter treats runs of letters and digits as words, preserves your line breaks and spacing structure, and handles mixed input, so a pasted SQL column list, a shouty email or a spreadsheet of product names all convert cleanly in one pass. Acronyms inside Title Case stay as you typed them in most cases, but give proper nouns a quick review, because no converter can know that "NASA" must stay uppercase while "nasa" in a sentence should not.
A note on style guides
Headline case is not one rule. AP style capitalises words of four letters or more, Chicago capitalises most words except articles and short prepositions, and many web teams simply use sentence case for everything because research shows it reads faster on screens. The converter gives you the consistent mechanical result instantly; choosing which convention your brand follows is the editorial decision on top, and consistency across your site matters more than which convention you pick.
For developers, the same consistency argument applies to code: pick the case each language community expects, camelCase in JavaScript, snake_case in Python, PascalCase for classes in C#, and convert legacy names in bulk rather than renaming by hand and breaking references.
Learn: how to use the Case Converter
- Type or paste your text in the top box.
- Click a case style. The converted text appears below instantly, and it keeps updating if you edit the original.
- Copy the result or download it as a text file.
Features
- 13 styles: upper, lower, Title Case, sentence case, capitalize each word, alternating, inverse, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and dot.case
- Smart Title Case keeps small words like "the" and "and" lowercase in the middle of a heading
- Remove extra spaces mode cleans pasted text
- Live conversion, copy and download
Worked example
Input: the lord of the rings. Title Case gives The Lord of the Rings, camelCase gives theLordOfTheRings, and snake_case gives the_lord_of_the_rings.
Frequently asked questions
What is the difference between Title Case and Capitalize Each Word?
Capitalize Each Word uppercases every word. Title Case follows headline style guides and keeps minor words (a, an, the, and, of, to) lowercase unless they start the heading.
Which case do programmers use for variables?
camelCase and PascalCase are common in JavaScript and Java, snake_case in Python and databases, kebab-case in URLs and CSS classes, and CONSTANT_CASE for constants.
Does conversion change my original text?
No. Your original stays in the top box; the result is written to the second box.
Can it fix text typed in ALL CAPS?
Yes. Paste the shouting text and pick lowercase or Sentence case to make it readable again.
What is the difference between camelCase and PascalCase?
Both join words without separators. camelCase starts with a lowercase letter, like userProfileName, and is used for variables and functions. PascalCase starts with a capital, like UserProfileName, and is used for classes and components.
Does Title Case capitalise every word?
This converter capitalises the first letter of every word. Some editorial style guides, like AP and Chicago, keep short words such as 'and', 'of' and 'the' lowercase in the middle of a title, so give proper nouns and small words a quick check afterwards.
Can I convert a whole list at once?
Yes. Paste the entire list or document, choose a case, and every line is converted with its line breaks preserved. That is how developers convert a column of names into variables in one pass.
Related tools
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