U+0178 "Ÿ" Latin Capital Letter Y with Diaeresis Unicode Character
Unicode Version 17.0
Ÿ
U+0178 "Ÿ" Latin Capital Letter Y with Diaeresis is a rarely used but historically important character, primarily employed in proper names and loanwords in French and other languages to indicate that the letter Y is pronounced separately from a preceding vowel, as in the name "L'Haÿ-les-Roses." It also appears in transliterations of certain Germanic and Slavic words and is occasionally used in Welsh orthography. Unlike the more common diaeresis on letters like Ë or Ï, this character is not widely supported in standard typography, often requiring special encoding or font support. Its inclusion in Unicode ensures that specialized textual representations remain digitally available and correctly rendered across systems.
General Properties
| Code Point | U+0178 |
| Version Added | 1.1 |
| Name | Latin Capital Letter Y with Diaeresis |
| Unicode 1.0 Name | Latin Capital Letter Y Diaeresis |
| Block | Latin Extended-A |
| General Category | Uppercase Letter |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Left To Right |
| Decomposition Type | Canonical |
| Decomposition Mapping | "Y" U+0059 Latin Capital Letter Y "̈" U+0308 Combining Diaeresis |
Encodings
| HTML Decimal Encoding | Ÿ |
| HTML Hex Encoding | Ÿ |
| UTF-8 Encoding | 0xC5 0xB8 |
| UTF-16 Encoding | 0x0178 |
| UTF-32 Encoding | 0x00000178 |
| C/C++/Java Escape | \u0178 |
Unicode Properties
| NFC Quick Check | Yes |
| NFKC Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Alphabetic |
| Uppercase | Yes |
| Simple Lowercase Code Point | "ÿ" U+00FF Latin Small Letter Y with Diaeresis |
| Lowercase Code Point | "ÿ" U+00FF Latin Small Letter Y with Diaeresis |
| Simple Case Folding | "ÿ" U+00FF Latin Small Letter Y with Diaeresis |
| Case Folding | "ÿ" U+00FF Latin Small Letter Y with Diaeresis |
| Cased | Yes |
| Changes When Casefolded | Yes |
| Changes When Casemapped | Yes |
| Changes When Lowercased | Yes |
| Changes When NFKC Casefolded | Yes |
| NFKC Casefold | "ÿ" U+00FF Latin Small Letter Y with Diaeresis |
| NFKC Simple Casefold | "ÿ" U+00FF Latin Small Letter Y with Diaeresis |
| Script | Latin |
| Script Extensions | Latin |
| Indic Syllabic Category | Other |
| ID Start | Yes |
| XID Start | Yes |
| ID Continue | Yes |
| XID Continue | Yes |
| Alphabetic | Yes |
| Vertical Orientation | Rotated |
| Grapheme Base | Yes |
| Grapheme Cluster Break | Other |
| Word Break | Alphabetic letter |
| Sentence Break | Upper |