Case Converter
Convert text without reloading the page.
Text tool
Text Case Converter
Format text for writing, publishing, and URLs.
All tools
Related Tools
Keep editing, checking, and preparing your text.
How To Use The Case Converter
Paste or type your text into the input box, then press the button for the style you want: Uppercase turns every letter capital, Lowercase makes every letter small, Title Case capitalises the first letter of each word, Sentence case capitalises only the first letter of the text, and Slug produces a lowercase, hyphen-separated string for URLs. The result replaces the text in the box, and the Copy button puts it on your clipboard so you can paste it straight into a document, a CMS field, or your code.
What Letter Case Actually Is
"Case" describes whether letters are written as capitals (uppercase) or small letters (lowercase), and the pattern of capitalisation across a phrase. Beyond the everyday upper and lower forms, programmers and editors use named conventions such as Title Case for headlines, Sentence case for body text, camelCase and snake_case for variable names, and kebab-case for URLs and file names. Each style is just a rule for which letters are capital and how words are joined. Converting between them is a quick way to make text fit the convention a headline, an API, or a web address expects.
The Case Styles At A Glance
The table below shows the same example phrase, "the quick brown fox", rendered in each common case style so you can see exactly how the letters and word separators change.
| Case style | Example output | Typical use |
|---|---|---|
| UPPERCASE | THE QUICK BROWN FOX | Emphasis, acronyms, warnings |
| lowercase | the quick brown fox | Casual text, tags, hashtags |
| Title Case | The Quick Brown Fox | Headlines and titles |
| Sentence case | The quick brown fox | Body text and descriptions |
| camelCase | theQuickBrownFox | Variables in JS, Java, C# |
| snake_case | the_quick_brown_fox | Variables in Python, Ruby |
| kebab-case | the-quick-brown-fox | URL slugs, CSS classes, files |
Notice that the words and their order never change between styles; only the capitalisation and the spaces or separators between words do.
Worked Example: A Headline Into A URL Slug
Suppose you write the article title How To Bake Sourdough Bread. For the on-page heading you want Title Case, which is exactly how it reads. To build the page address, switch to the slug style and you get how-to-bake-sourdough-bread, a clean lowercase string with hyphens between words and no capital letters or spaces that could break the link. The slug carries the same words as the title, just formatted so a browser, a CMS, and a search engine can all read it without trouble.
Why This Tool Is Useful
Re-typing a heading in capitals, fixing the casing of text pasted from a spreadsheet, or turning a title into a URL slug by hand is slow and error-prone. This converter does it in one click. Writers use it to normalise headlines and clean up text copied from email or PDFs; developers use it to switch a label between camelCase, snake_case, and kebab-case to match a language or framework; and anyone publishing online can turn a title into a tidy slug for a link. Because every style sits behind its own button, you can try several and keep whichever reads best, without touching the underlying words.
Accuracy And Privacy
All of the conversion happens locally in your browser with JavaScript, so nothing you paste is uploaded, logged, or stored on any server; close the tab and the text is gone. One thing automated casing cannot judge is intent: it does not know that iPhone, NASA, or a person's name has a fixed style, so after a Title Case or Sentence case conversion give proper nouns, brand names, and acronyms a quick review and fix any letters the rule changed incorrectly.
FAQ
What are the rules for Title Case?
Title Case capitalises the first letter of each significant word, which is the style used for headlines and book titles. This tool capitalises the first letter of every word. Strict editorial style guides keep short words such as a, an, the, and, or, of, and to in lowercase unless they begin the title, so review long headings by hand if you follow a specific guide like AP or Chicago.
When should I use camelCase versus snake_case in code?
It depends on the language convention. JavaScript, Java, and C# use camelCase for variables and functions, where the first word is lowercase and each later word starts with a capital letter and no spaces, like userName. Python and Ruby prefer snake_case, where words are lowercase and joined by underscores, like user_name. Picking the convention your language expects keeps your code consistent and readable for other developers.
What is kebab-case used for?
kebab-case writes words in lowercase joined by hyphens, like my-page-title. It is the standard for URL slugs, CSS class names, and file names because hyphens are safe in web addresses and easy to read. Search engines treat hyphens as word separators, so a kebab-case slug is friendlier for SEO than one joined with underscores or spaces.
Does converting the case change the words themselves?
No. Changing case only changes which letters are capital or lowercase and, for the slug and snake_case styles, replaces the spaces between words with hyphens or underscores. The actual words and their order stay exactly the same, so you can convert back and forth without losing any text.
Is my text uploaded anywhere?
No. Every conversion runs locally in your browser using JavaScript, so the text you paste never leaves your device and is not sent to any server. You can safely convert drafts, private notes, or internal labels.