What is a case converter?
A case converter is a text tool that switches letters between uppercase and lowercase according to a rule, such as capitalising every major word (Title Case) or only the first word of each sentence (Sentence case). It saves you retyping a heading that was written in caps lock, a list of names that came out of a spreadsheet in lowercase, or a product title that needs to match a style guide.
This online case converter also covers the "programmer cases": camelCase, PascalCase, snake_case and kebab-case, which join words without spaces for code, file names and CSS classes. And it makes a clean URL slug, the readable part of a web address. Every format is generated live from the same input, so you can compare them side by side.
How to convert text case online
- Add your text. Type or paste into the "Your text" box, or tap Paste to pull in whatever is on your clipboard (your browser may ask for permission; if it refuses, use Ctrl+V or Cmd+V).
- Read the results. All nine formats update on every keystroke: Sentence case, Title Case, UPPER CASE, lower case, kebab-case, snake_case, camelCase, PascalCase and URL slug.
- Copy the one you need with the Copy button on its row.
- Start over with Clear, which empties the box and puts the cursor back in it.
Line breaks are kept in Sentence, Title, UPPER and lower case, so you can convert a whole list of headings in one go. The programmer cases and the slug join everything into a single string.
Every text case style with examples
Here is the same input, the best free tools for small business, in each format the tool produces:
| Case | Result | Typical use |
|---|---|---|
| Sentence case | The best free tools for small business | Body text, UI labels, most headings on modern sites |
| Title Case | The Best Free Tools for Small Business | Article titles, book and film names, YouTube titles |
| UPPER CASE | THE BEST FREE TOOLS FOR SMALL BUSINESS | Short labels, buttons, acronyms, warnings |
| lower case | the best free tools for small business | Hashtags, usernames, casual aesthetic captions |
| kebab-case | the-best-free-tools-for-small-business | CSS classes, file names, HTML attributes |
| snake_case | the_best_free_tools_for_small_business | Python variables, database columns, JSON keys |
| camelCase | theBestFreeToolsForSmallBusiness | JavaScript and Java variables and functions |
| PascalCase | TheBestFreeToolsForSmallBusiness | Class names, React components, C# types |
| URL slug | the-best-free-tools-for-small-business | Page URLs, blog post addresses, usernames |
Kebab-case and the URL slug look identical for plain words, but they differ with punctuation and accents. "Café menu: 2026!" becomes café-menu:-2026! in kebab-case (punctuation is kept) and cafe-menu-2026 as a slug (accents converted, symbols removed). Use the slug for anything that goes in a URL.
Title case rules: which words get capitals?
Title case capitalises the main words of a heading and leaves short function words in lowercase. The title case converter here capitalises the first word of every line and every word except this list of small words: a, an, the, and, or, but, of, in, on, at, to, for, by, vs, via.
Style guides disagree on the details:
- AP style (news) capitalises words of four letters or more, including prepositions like "With" and "From".
- Chicago style (books) lowercases all prepositions regardless of length, and always capitalises the first and last word.
- APA style (academic) capitalises words of four letters or more and both parts of hyphenated words.
The tool follows a simple common rule that suits most blog posts and video titles. If you follow a specific guide, check two cases by hand: a short word at the end of a title ("What Are You Looking For") and words after a colon ("Instagram Growth: A Beginner's Guide").
Sentence case works differently: the tool lowercases everything, then capitalises the first letter of the text and the first letter after each full stop, question mark or exclamation mark.
camelCase, snake_case and kebab-case for programmers
Programmer cases exist because most languages do not allow spaces in names. The converter splits your input into words on spaces, underscores, dashes and lowercase-to-uppercase boundaries, so it also converts between code styles: userProfileId, user_profile_id and user-profile-id all become each other.
- camelCase: JavaScript, TypeScript, Java and Swift variables and functions.
- PascalCase: classes in most languages, React and Vue component names.
- snake_case: Python and Ruby variables, SQL tables and columns, many REST APIs.
- kebab-case: CSS class names, HTML data attributes, npm package names, URLs.
SCREAMING_SNAKE_CASE (used for constants) is not a separate row, but you can make it in two steps: copy the snake_case result, paste it back in, and copy the UPPER CASE row.
When to use an upper case lower case converter
- Fix caps lock: paste a paragraph typed in all caps and copy the Sentence case version.
- YouTube and blog titles: write naturally, then copy Title Case so every video in a series looks consistent.
- Spreadsheet clean-up: a shop owner exports customer names in lowercase and converts the list to Title Case before printing labels.
- URL slugs: a blogger turns "10 Best Cafés in Jaipur (2026)" into
10-best-cafes-in-jaipur-2026. - Usernames and handles: generate a lowercase, dash-separated version of your brand name to check before you claim it.
- Developers: turn an API field list in snake_case into camelCase for a JavaScript object.
Case converter vs Word, Google Docs and Excel
| App | How to change case | What it offers |
|---|---|---|
| Microsoft Word | Select text, press Shift+F3 (Windows) or use Home, Change Case (Aa) | Sentence, lower, UPPER, Capitalize Each Word, tOGGLE |
| Google Docs | Format, Text, Capitalization | lowercase, UPPERCASE, Title Case |
| Excel / Google Sheets | Formulas =UPPER(A1), =LOWER(A1), =PROPER(A1) | UPPER, lower, capitalise every word |
| This tool | Paste once | All nine formats side by side, including code cases and slugs |
Built-in options are handy inside those apps. Note that Word's "Capitalize Each Word" and the spreadsheet PROPER() function capitalise every word, including "of" and "the", which is not true title case. This online case converter keeps small words lowercase and works for text from any app, including your phone.
Hashtags: use PascalCase for readability
Multi-word hashtags are easier to read when each word starts with a capital, for example #SmallBusinessIndia instead of #smallbusinessindia. Screen readers also read capitalised hashtags word by word rather than as one long jumble. Hashtags are not case sensitive on Instagram, TikTok or X, so the capitals do not change which posts the tag reaches. Type the phrase here, copy the PascalCase row and add the #. The hashtag cleaner can tidy a full set.
Common mistakes when changing text case
- Losing proper nouns in Sentence case. Because everything is lowercased first, names, brands and "I" lose their capitals: "I love Instagram" becomes "I love instagram". Fix these by hand after converting.
- Breaking acronyms and brand spellings in Title Case. Each word is capitalised and the rest lowercased, so "SEO" becomes "Seo" and "iPhone" becomes "Iphone". Re-check acronyms.
- Using all caps for long text. UPPER CASE is harder to read in paragraphs and screen readers may spell out some all-caps words letter by letter. Keep it for short labels.
- Using kebab-case for URLs. It keeps punctuation, which can break links. Use the URL slug row.
- Expecting the slug to keep non-Latin scripts. The slug keeps only a-z, 0-9 and dashes. Text in Hindi, Arabic or other non-Latin scripts is dropped, so write a short English or transliterated slug instead.
Is this online case converter private?
Yes. Conversion runs entirely in your browser with JavaScript; your text is not uploaded, logged or saved. The Paste button only reads your clipboard when you tap it, and closing the tab clears everything.
Using case styles on your link-in-bio page
Consistent button labels make a bio page easier to scan: pick Title Case or Sentence case and use it for every link. Your page URL on Biolinko is a slug too (biolinko.me/yourname), so the slug row is a quick way to test a clean handle. For styled bio text, try the Instagram fonts generator, check length with the character counter, and claim your page when ready.
Updated October 8, 2026