Case Converter
Paste your text and change it to UPPER, lower, Title or Sentence case in one click. Pick the letter language for correct Turkish results.
How it works
- Write or paste your text in the left panel.
- Pick a case: UPPER, lower, Title, Sentence, iNVERT or aLtErNaTe.
- Copy the result or download it as a txt file.
Why this tool
- Six cases: UPPER, lower, Title, Sentence, iNVERT, aLtErNaTe.
- Letter language switch: Turkish İ/ı rule or English.
- Move the result back to the input and convert again.
- A word and character count under the result.
- The text stays in your browser. There is no upload.
Turkish has two letters where English has one. The capital of i is İ. The capital of ı is I. Computers do not know this by default. The general Unicode rule turns i into I, because the rule follows English. The word "işlem" then becomes "ISLEM" and the reader sees the wrong word.
This tool lets you pick the letter language. With Turkish selected, the browser applies the Turkish locale rule: i becomes İ and ı becomes I. The letters ş, ç, ğ, ö and ü also change correctly. Pick English for code, file names and English text, where the classic behaviour is what you want.
There are six cases. UPPER and lower are clear. Title raises the first letter of each word, which helps for headings and menu labels. Sentence raises the letter after a full stop or a line break, which is the fastest way to repair a paragraph typed in capitals. iNVERT flips each letter and rescues text typed with Caps Lock on. aLtErNaTe writes lower and upper letters in turn.
One warning: no automatic case knows proper nouns. After Sentence case you must fix names like "ankara" by hand. Title case also raises small words such as "and", and your style guide may want them lower.
The conversion runs in your browser. The text does not go to a server.
Frequently asked questions
Why do Turkish letters break in other tools?
Most tools apply the English rule and turn "istanbul" into "ISTANBUL". With the Turkish letter language, i becomes İ and ı becomes I. The correct form is "İSTANBUL".
Which letters does Title case raise?
It raises the first letter of every word. It also raises a letter after a hyphen, a bracket or a quote. It does not keep small words like "and" lower. Fix those by hand.
How does Sentence case work?
It raises the first letter after a full stop, an exclamation mark, a question mark or a line break. All other letters go lower. You must fix proper nouns by hand.
Is there a length limit?
Not in practice. The browser slows down at a few hundred thousand characters. Convert a book-length text in parts.
Does my text go to a server?
No. The conversion runs in your browser. The text stays on your computer.
What are iNVERT and aLtErNaTe for?
iNVERT flips the case of every letter and repairs text typed with Caps Lock on. aLtErNaTe writes lower and upper letters in turn, mostly for social media.