Case Converter
Convert any block of text between eight case styles — including the programming ones — without retyping a word.
What the case Converter does
A case converter rewrites the capitalisation of text without changing the words themselves. Paste a paragraph, click a style, and the tool rebuilds the string character by character in JavaScript. It covers the four styles writers need — uppercase, lowercase, title case and sentence case — plus the five that developers need: camelCase, PascalCase, snake_case, kebab-case and an alternating style for the occasional joke.
The two that most tools get wrong are title case and sentence case. Title case here follows the
common editorial convention of capitalising every word except short articles, conjunctions and
prepositions (a, and, of, the, to
and friends), while always capitalising the first word. Sentence case lowercases everything first,
then re-capitalises after a full stop, question mark, exclamation mark or line break — so a
heading pasted in SHOUTING CAPS comes back as ordinary prose rather than one long lowercase run.
The programming styles work differently again. They split your text into words at spaces,
underscores, hyphens and existing capital-letter boundaries, drop everything that is not a letter or
digit, then rejoin. That means User Profile Image, user-profile-image and
userProfileImage all convert cleanly into each other, which is what you want when you
are moving a field name between a spreadsheet, a database column and a JavaScript object.
How to use it
- Paste or type your text into the input box. There is no length limit beyond your browser's memory.
- Click the case style you want. The result appears immediately in the box below.
- Use Copy result to put it on the clipboard, or Send back to input to chain another conversion on top.
A worked example
Say you have a column heading exported from a spreadsheet:
Monthly Recurring Revenue (USD)Clicking each button in turn gives you:
| Style | Result |
|---|---|
| Title Case | Monthly Recurring Revenue (USD) |
| Sentence case | Monthly recurring revenue (usd) |
| camelCase | monthlyRecurringRevenueUsd |
| snake_case | monthly_recurring_revenue_usd |
| kebab-case | monthly-recurring-revenue-usd |
The last three are the ones worth chaining: convert the heading to snake_case for your database column, then paste the same heading in again and convert to camelCase for the JavaScript property.
Frequently asked questions
Does title case follow AP or Chicago style?
It follows the common convention shared by both: capitalise every word except short articles, conjunctions and prepositions of three letters or fewer, and always capitalise the first word. AP and Chicago disagree on edge cases such as prepositions of four or more letters, so check your house style if you are working to a strict guide.
Will it break my accented characters or emoji?
No. Conversion uses the browser's own Unicode-aware toUpperCase and toLowerCase, so accented letters, Cyrillic, Greek and other scripts convert correctly. Emoji and punctuation are left untouched. The programming styles do strip non-alphanumeric characters, because identifiers cannot contain them.
Is there a limit on how much text I can convert?
There is no artificial limit. Because everything happens in your browser, the practical ceiling is your device's memory. Documents of several hundred thousand words convert in well under a second on a normal laptop.
Is my text sent anywhere?
No. The page contains the entire conversion logic. Once it has loaded you can disconnect from the internet and the tool still works, which is the simplest proof that nothing is being uploaded.