Convert Case
Upper/lower/sentence case.
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Text cases and where each belongs
Case conventions carry meaning. Prose uses sentence case. Headlines in many style guides use title case, capitalising principal words but not short articles and prepositions. Programming has its own set: camelCase for JavaScript variables, PascalCase for class names, snake_case for Python and database columns, kebab-case for URLs and CSS classes, and UPPER_SNAKE_CASE for constants.
Converting between them is less mechanical than it looks. Turning a heading into title case requires knowing which words are minor. Turning a phrase into camelCase requires detecting word boundaries that may be spaces, hyphens, or underscores. And uppercasing is language-dependent — the Turkish dotless i and the German sharp s both behave differently from what English rules would predict, which is why naive uppercase functions have caused real bugs.
Why we built this tool
You need this whenever text crosses a boundary: reformatting a headline that arrived in ALL CAPS, converting a spreadsheet column into database field names, fixing a paragraph typed with caps lock on, or generating URL slugs from article titles.
That text is usually unpublished copy or internal data. There is no reason for a case change — pure string manipulation — to involve a network request at all, so ours does not make one. Everything runs in your browser, instantly, with no length limit and no storage. It works with the connection off, which is the sort of small reliability that makes a utility worth keeping in a bookmark.
Tips and common mistakes
- Title case rules differ between style guides; check whether yours capitalises short prepositions.
- Acronyms and brand names survive no automatic conversion — fix them by hand afterwards.
- URL slugs should be lowercase kebab-case, with accents transliterated rather than encoded.
- Uppercasing behaves differently in Turkish and German, so avoid it for user-facing text in those languages.
Open Convert Case with a link
Convert Case can be handed its input by the link that opens it, so the page arrives with the work already done. This is meant for assistants and scripts: if a chatbot, an editor extension, or a command-line agent already holds your content, it can build a link instead of asking you to copy and paste into a box.
The payload rides in the fragment — the part of a URL after the #. Browsers never send the fragment to a server, so anything handed over this way stays on your device exactly as a dropped file would. A link that uses the query string instead is rewritten into the fragment by the page before any analytics or ad script can read the address.
Prefix any field with gz — #gztext= — to pass it as gzip-compressed base64url, which fits roughly five to ten times more into the same link. Links stay reliable up to about 8,000 characters; past that, chat apps and address bars start truncating them, and the page says so rather than loading half a document.
One exception to the privacy rule: ?url= tells the page to download the input from an address. That request goes from your browser straight to that server — not through ours — but it does leave your device, and it only works if the server allows cross-origin requests.
#text=— the text to work on
Example: https://mygadgets.ink/tools/convert-case/#text=...
Quick start: using Convert Case
- Paste your text into the input above.
- Choose the target case from the options.
- Check the result, especially any acronyms or proper nouns that need to stay as they are.
- Fix those by hand — no automatic converter knows your brand names.
- Copy the converted text.
Clean up spacing afterwards with Remove Extra Spaces, or strip styling with Remove Formatting.