Uppercase / Lowercase Converter

Convert your text to UPPERCASE, lowercase, Title Case and Sentence case, or invert the case of every letter — fully compliant with the Turkish i/İ rule.

Runs 100% in your browser — your data is never sent to a server.

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Frequently Asked Questions

Yes. In Turkish, the uppercase of i is dotted İ, and the uppercase of ı is dotless I — a plain English-rule toUpperCase()/toLowerCase() misses this and turns "istanbul" into "ISTANBUL" (the correct form is "İSTANBUL"). This tool uses the tr-TR locale, so the conversion always follows the correct Turkish rule.

Title Case capitalizes the first letter of every word and lowercases the rest (e.g. "turkish character test" → "Turkish Character Test"). Sentence case only capitalizes the first letter of each sentence (ending in ., ! or ?) and lowercases everything else.

No. All conversions run instantly in your browser with JavaScript; your text is never sent to OpenMoon's servers or any third party.

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