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Case Converter

Convert text to upper, lower, title, sentence, or inverse case.

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Case Converter guide

Change the capitalization of headings, lists, notes, labels, or imported text with one consistent browser-based transformation.

What this tool does

The Case Converter provides five transformations. Uppercase and lowercase use the browser's locale-aware character methods. Title Case first lowers the text and then capitalizes every word boundary. Sentence case lowers the text and capitalizes a letter at the beginning or after sentence-ending punctuation. Invert Case switches each letter between its uppercase and lowercase form.

These are deterministic character transformations, not editorial rewriting. They do not correct spelling, decide which words deserve emphasis, or apply a publication's custom headline rules. Acronyms and brand names may need manual restoration after Title Case or Sentence case because the tool cannot infer the writer's intended styling.

How to use it

  1. Paste or type the source text.
  2. Select the capitalization style you need.
  3. Review names, acronyms, and product terms after conversion.
  4. Apply another case style if you want to compare results.
  5. Copy the converted text using the provided control.

Benefits

  • Five distinct case transformations
  • Locale-aware upper- and lowercase conversion
  • Sentence-boundary capitalization for ordinary prose
  • Character-by-character inverse case handling
  • Copy fallback for browsers with restricted clipboard access

Choosing a case style

Uppercase is useful for short labels but can reduce readability in long paragraphs. Lowercase helps normalize inconsistent imported data. Title Case is suitable as a starting point for headings, while Sentence case fits prose and labels where only the first word should begin with a capital. Invert Case is mainly useful for correcting text typed with the wrong Caps Lock state or testing case-sensitive data.

Title rules differ between editorial styles. This tool capitalizes every word rather than maintaining a list of articles, conjunctions, or prepositions to keep lowercase. Review the result whenever a specific style guide, trademark, code identifier, or legal name must be preserved exactly.

FAQ

No. It applies a predictable rule that capitalizes each word boundary. Editorial styles treat short articles and prepositions differently, so publication-specific headings still need review.

Title and sentence transformations lower the source before capitalizing selected letters. The tool cannot know that a sequence such as API, NASA, or a brand name should retain special capitalization.

Lowercase changes every cased letter to its lower form. Sentence case then capitalizes the beginning of the text and letters following a detected sentence boundary.

No. The transformations target letter case while preserving existing punctuation, whitespace, and line breaks. Only the cased characters are replaced.

No. Conversion and copying happen in your browser. The source and result are not sent to or saved by ToolSeta.

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