Case Converter
Convert English text between common capitalization and identifier formats.
Case Converter turns pasted text into UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case, kebab-case, and CONSTANT_CASE. It only changes ASCII letters, so Chinese, Japanese, and other CJK characters pass through unchanged.
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Who this tool is for
Useful for cleaning English headings, code identifiers, spreadsheet fields, filename drafts, and pasted text.
Common mistakes
Before using Case Converter, check that the inputs and destination workflow match. These issues can make an output look useful while still being wrong for the real task.
- Do not expect it to understand proper-noun capitalization.
- Do not use it on code blocks where exact formatting matters.
- Do not treat automatic Title Case as a publishing style guide.
Limitations
Case Converter is a browser-based helper for quick preparation, cleanup, or checking. Keep the original material and review important output before using it in a formal workflow.
- It mainly transforms ASCII letters.
- It does not fix grammar or spelling.
- CJK text passes through unchanged.
How to use
- Paste the text you want to convert into the input textarea.
- Press any conversion button to update the output immediately.
- Try another format by pressing a different conversion button.
- Copy the result or clear the text when you are done.
Use cases
- Turn a heading into Title Case or Sentence case.
- Convert variable names to camelCase, snake_case, or kebab-case.
- Quickly uppercase or lowercase an English text fragment.
- Clean copied text from forms, spreadsheets, or documents.
Content and verification review:
How to verify a Case Converter result before relying on it
This section covers what Case Converter’s eight modes actually do to text outside the plain A–Z range — accented letters and other non-ASCII characters — since the tool converts case using an ASCII-only method on every locale version of the page.
Confirm the basic conversions with plain English text
Type “hello world” and click Title Case: the result is “Hello World.” Click camelCase instead: the result is “helloWorld.” Both are straightforward to check visually and confirm the buttons are wired to the modes you expect.
Accented and non-Latin characters are not converted — only plain A–Z is
Type “café résumé” and click UPPERCASE: the result is “CAFé RéSUMé,” not “CAFÉ RÉSUMÉ” — the accented “é” characters pass through untouched because the conversion only matches the plain ASCII ranges A–Z and a–z. The same limitation applies to Title Case and Sentence case: a phrase like “à la carte” at the start of a sentence will not get its leading character capitalized correctly by Sentence case.
snake_case and kebab-case only replace spaces — not punctuation you didn’t expect
Converting “API Response (v2)” to snake_case produces “api_response_v2” — the parentheses are treated as separators and dropped, not preserved or escaped. Only the most recently clicked mode’s result is ever shown in Output, with no history of previous conversions, so if you need two different case styles from the same input, convert and copy each one separately before switching modes.
Acceptance checklist
- The source text is plain ASCII English, or you have accepted that accented letters (é, à, ü, etc.) will not be uppercased, lowercased, or capitalized correctly.
- Punctuation inside the text (parentheses, slashes, periods) has been checked against snake_case/kebab-case output, since it is dropped as a separator, not preserved.
- Only the current Output value is relied on — a second case style needed from the same input has been copied out before clicking a different mode.
- Sentence case has been visually checked on text that starts with a non-ASCII letter, since that first character will not be capitalized.
Who is it for
- Useful for cleaning English headings, code identifiers, spreadsheet fields, filename drafts, and pasted text.
Real examples
Example 1
Convert field names to snake_case.
Example 2
Turn a headline draft into Title Case before manual review.
Example 3
Convert all-caps pasted text into more readable sentence case.
Good to know
- Do not expect it to understand proper-noun capitalization.
- Do not use it on code blocks where exact formatting matters.
- Do not treat automatic Title Case as a publishing style guide.
- It mainly transforms ASCII letters.
- It does not fix grammar or spelling.
- CJK text passes through unchanged.
FAQ
- Will Chinese text change?
- No. Chinese and most CJK characters pass through unchanged.
- Does it fix grammar?
- No. It only changes case and identifier formats.
- Can it be used for code variables?
- Yes for drafts, but review production code manually.
- Is Title Case always correct?
- No. Style guides differ.
- Is data uploaded?
- No. Text is processed in the browser.
Privacy & local processing
🔒 This tool runs entirely in your browser. No data is uploaded to any server.
This tool runs mainly in your browser. The content you enter is not sent to FunnyTools servers.
Trust & usage note
This tool runs mainly in your browser. Your input is not actively uploaded to a server. Avoid entering highly sensitive data. Results are for reference only.
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