Overview
Capitalisation carries meaning, and getting it wrong is embarrassingly easy. A heading typed with Caps Lock left on, a paragraph pasted from a PDF in all capitals, a database column that needs to become a JavaScript variable name — each of these is a small job that is miserable to do by hand and trivial for a machine. This converter does all of them in one click, across thirteen formats, without reformatting anything you did not ask it to touch.
The thirteen conversions fall into three families. There are the plain styles for prose — upper, lower, sentence and title case. There are the naming conventions programmers live by — camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE — which are applied intelligently: the tool first understands where your words begin and end, whether they were separated by spaces, underscores, hyphens or existing capital letters, and then rebuilds them in the target style. And there are the cleanup and novelty styles: collapse runaway spaces, strip line breaks, alternating case, and inverse case.
What is case conversion?
Case conversion is changing how letters are capitalised without changing the words themselves. The simplest versions are mechanical: make everything big, or make everything small. The interesting ones encode structure. In camelCase, the humps tell a reader where one word ends and the next begins, because the spaces have been removed. In snake_case, underscores do that job instead. CONSTANT_CASE is a long-standing signal in programming that a value is fixed and should not be reassigned.
Sentence case and title case are where people argue, because style guides differ. Sentence case capitalises the first word of each sentence and proper nouns — the shape of ordinary writing. Title case capitalises the important words of a heading while leaving short joining words such as 'and', 'of' and 'the' small in the middle. This tool follows that mainstream convention, and because conversion here is non-destructive, you can try both and keep the one your style guide prefers.
Features
- Thirteen conversions, one panel — every common prose style, programming convention and cleanup transform, one click each.
- Smart word splitting — camelCase, PascalCase and friends are rebuilt from the underlying words, so 'user_first-name' and 'userFirstName' both convert cleanly to any other convention.
- Mixed separators handled — spaces, underscores, hyphens and runs of punctuation are all treated as word boundaries where they should be.
- Separate input and output — your original text is never overwritten by a conversion; run several styles and compare before choosing.
- Chainable results — send the output back to the input with one button and apply a second conversion on top of the first.
- Live counts — characters and words for both input and output update as you type, so cleanups show exactly what they removed.
- Copy or download — take the result to your clipboard in one click, or save it as a plain text file.
Benefits
- No retyping — retyping a heading by hand invites fresh typos; converting the existing text cannot introduce them.
- Consistency across a project — one pass turns a file of mixed naming styles into a single convention a whole team can follow.
- Faster drafting — write naturally first, then style headings, variables and labels at the end in seconds.
- Cleaner pasted text — collapse-spaces and line-break removal rescue text mangled by PDFs, emails and spreadsheets.
Who can use it
Writers and editors use it to style headings, fix caps-lock accidents and prepare copy for a CMS. Developers use it constantly: renaming variables, converting database columns to object properties, generating URL slugs with kebab-case, or shouting constants into CONSTANT_CASE. Students use it for titles and references, and office workers for cleaning text out of documents.
How to use
- Type or paste your text into the Your text box on the left.
- Click the conversion you want. The result appears in the Converted text box on the right.
- Check the counts under the boxes if you need to confirm what changed.
- Click Copy result to take the converted text with you, or Download .txt to save it as a file.
- To convert the result again, click Use result as input and choose another style.
Frequently asked questions
Does converting overwrite my original text?
No. The input box keeps exactly what you typed, and every conversion writes to the separate output box. You can try all thirteen styles against the same original and keep whichever you like.
What is the difference between title case and sentence case?
Sentence case capitalises only the first letter of each sentence. Because it lowercases everything else first, names in the middle of a sentence lose their capital — give proper nouns a quick check afterwards. Title case capitalises the significant words in a heading while leaving short joining words small.
Can it convert camelCase to snake_case and back?
Yes, in every direction. The tool first splits the input into its underlying words — whether they were separated by spaces, underscores, hyphens or capital letters — and then rebuilds them in whichever convention you pick.
What does Collapse Spaces do?
It reduces every run of spaces and tabs to a single space, which is what you want after pasting text from PDFs or spreadsheets. The live counts show exactly how many characters it removed, so nothing happens silently.
What is alternating case for?
Mostly humour — the sPoNgEbOb style of mocking text. It is included for fun and for the rare design that wants it. Used sparingly, one hopes.
Is my text sent anywhere?
No. All conversion happens in your browser. There is nothing to upload and nothing to wait for, and closing the tab discards everything.
Conclusion
Capitalisation is a small thing until it is wrong. Restyle any text across thirteen conventions in one click each — no retyping, no typos, no waiting.