U+2102 "ℂ" Double-Struck Capital C Unicode Character
Unicode Version 17.0
ℂ
U+2102 "ℂ" Double-Struck Capital C is a typographic symbol from the letterlike symbols block, designed to represent the set of complex numbers in mathematical notation. It features a bold, blackboard bold style with an extra vertical stroke through the letter C, distinguishing it from the standard uppercase C. This character is commonly used in fields such as algebra, analysis, and number theory to denote the field of complex numbers, where numbers take the form a + bi with i as the imaginary unit. Its inclusion in Unicode allows for consistent digital representation across platforms and fonts, supporting precise mathematical communication.
General Properties
| Code Point | U+2102 |
| Version Added | 1.1 |
| Name | Double-Struck Capital C |
| Unicode 1.0 Name | Double-Struck C |
| Block | Letterlike Symbols |
| General Category | Uppercase Letter |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Left To Right |
| Decomposition Type | Font |
| Decomposition Mapping | "C" U+0043 Latin Capital Letter C |
Encodings
| HTML Decimal Encoding | ℂ |
| HTML Hex Encoding | ℂ |
| UTF-8 Encoding | 0xE2 0x84 0x82 |
| UTF-16 Encoding | 0x2102 |
| UTF-32 Encoding | 0x00002102 |
| C/C++/Java Escape | \u2102 |
Unicode Properties
| NFC Quick Check | Yes |
| NFD Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Alphabetic |
| Uppercase | Yes |
| Cased | Yes |
| Changes When NFKC Casefolded | Yes |
| NFKC Casefold | "c" U+0063 Latin Small Letter C |
| NFKC Simple Casefold | "c" U+0063 Latin Small Letter C |
| Script | Common |
| Script Extensions | Common |
| Indic Syllabic Category | Other |
| ID Start | Yes |
| XID Start | Yes |
| ID Continue | Yes |
| XID Continue | Yes |
| Alphabetic | Yes |
| Math | Yes |
| Other Math | Yes |
| Vertical Orientation | Rotated |
| Grapheme Base | Yes |
| Grapheme Cluster Break | Other |
| Word Break | Alphabetic letter |
| Sentence Break | Upper |