Why does Istanbul become İstanbul?

In Turkish, lowercase i is a dotted letter whose uppercase form keeps the dot: İ. So the city name istanbul correctly title-cases to İstanbul. A plain ASCII toUpperCase would wrongly produce Istanbul with a dotless capital.

What happens to the dotless ı?

Lowercase ı (dotless i) uppercases to plain I in Turkish. So a word like ışık becomes Işık. This is the mirror image of the dotted-i rule and is the other half of the Turkish I problem.

How is each word capitalized?

The tool uppercases only the first cased character of each word using Turkish locale rules, then lowercases the rest. Whitespace and punctuation between words are preserved exactly.

Does it handle other Turkish letters like ç and ş?

Yes. The conversion uses the Turkish locale throughout, so ç, ğ, ö, ş, and ü all map to their correct upper and lower forms alongside the special i and ı handling.

Is this the same as a normal title-case tool?

No. Generic title-case tools use ASCII or English-locale rules and mishandle the Turkish dotted and dotless i. This tool applies the tr-TR locale specifically so capitalization is linguistically correct.

Turkish Title Case — Gera Tools

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Title case that respects the Turkish I

Title-casing Turkish text is a famous trap for software. The reason is the language’s two distinct letters: the dotted i and the dotless ı. Their uppercase forms differ from the ASCII default, so a naive toUpperCase turns istanbul into the wrong Istanbul instead of the correct İstanbul. This tool applies the proper Turkish locale rules so every word is capitalized correctly.

How it works

For each word, the tool capitalizes only the first cased letter and lowercases the rest, using Turkish locale mappings:

lowercase i (dotted) → uppercase İ (dotted)
lowercase ı (dotless) → uppercase I (plain)
uppercase I → lowercase ı, uppercase İ → lowercase i

Internally it converts case with the tr-TR locale and explicitly fixes the i/ı pair before applying toLocaleUpperCase. Whitespace between words is preserved so spacing and line breaks survive unchanged.

Example

input:  istanbul ışık ılgın iyi
output: İstanbul Işık Ilgın İyi

Notice istanbul gains a dotted capital İ, while ışık and ılgın take a plain I. An ASCII title-case tool would get all four words wrong.

Tips and notes

Use this whenever you generate Turkish headings, names, or labels programmatically — the I bug is easy to ship and hard to spot in review.
The tool only touches the first letter of each word; it does not force ALL CAPS or sentence case.
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