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littlekit.app

Case converter

Convert text to uppercase, lowercase, title case, or simple sentence case, then copy or download the result.

Processed on your device

How it works & useful details

How to use this tool

Paste text and select a case style. Spacing, punctuation, and original line endings remain in place.

How the result is calculated

Uses default Unicode case mappings, not locale-specific Turkish or other language rules. Title case lowercases every word then capitalizes its first character, including small words. Sentence case lowercases everything, then capitalizes the next letter at the start and after . ! or ?. It cannot recognize abbreviations, names, acronyms, or grammatical sentence boundaries.

Words are runs of Unicode letters or numbers, with combining marks and internal straight or curly apostrophes. Hyphens split words. Text is NFC-normalized for counting; Chinese and Japanese runs are not dictionary-segmented.

Up to 500,000 UTF-16 code units per input. Text stays on your device.

About this tool

Case converter switches text to uppercase, lowercase, title case, or simple sentence case. It is handy for headings, form fields, and data cleanup where casing needs to be consistent.

Converting runs locally, and the original text is untouched. Title case and sentence case follow simple, predictable rules rather than full grammar analysis.

How to use it

  1. Paste the text.
  2. Choose the case style you need.
  3. Compare the result with the original.
  4. Copy or download the converted text.

Worked example

Input:          the QUICK brown fox. it jumped!
UPPERCASE:      THE QUICK BROWN FOX. IT JUMPED!
lowercase:      the quick brown fox. it jumped!
Title Case:     The Quick Brown Fox. It Jumped!
Sentence case:  The quick brown fox. It jumped!

Title and sentence case lowercase the text first, which is how "QUICK" becomes "Quick" and "quick". That is what you want for text typed with caps lock, but it also lowercases acronyms and names. Review the output for words like NASA, iPhone, or McDonald.

Title case rules differ

Style guides disagree on which small words to capitalize in headlines. AP, Chicago, and APA style all keep short articles and prepositions like "a", "of", and "in" lowercase except at the start. This tool capitalizes every word, a simple rule that is predictable and easy to correct by hand. For editorial headlines, fix the small words afterwards.

Case mapping uses Unicode's default rules, so accented and non-Latin letters convert correctly: é becomes É, and ß becomes SS in uppercase. Language-specific rules, such as the Turkish dotted and dotless i, are not applied.

Frequently asked questions

How does title case handle small words?

Common short words are lowercased unless they are first or last, following simple conventions rather than a language-specific style guide.

Does it change accents or non-Latin scripts?

Case folding applies where the script defines it; characters without case are left as they are.

What is the limit?

Up to 500,000 characters per conversion.

Does it change line breaks or punctuation?

No. Only letter case changes. Spacing, punctuation, and line endings stay exactly as they were.