U+211A "ℚ" Double-Struck Capital Q Unicode Character
Unicode Version 17.0
ℚ
U+211A "ℚ" Double-Struck Capital Q is a mathematical symbol representing the set of all rational numbers, which includes any number that can be expressed as a fraction of two integers, with the denominator not equal to zero. It belongs to the Letterlike Symbols block of Unicode and is commonly used in mathematics, particularly in number theory and algebra, to denote the field of rationals. The double-struck or blackboard bold style distinguishes it from ordinary alphabetic characters, allowing for clear notation in typesetting and mathematical discourse.
General Properties
| Code Point | U+211A |
| Version Added | 1.1 |
| Name | Double-Struck Capital Q |
| Unicode 1.0 Name | Double-Struck Q |
| Block | Letterlike Symbols |
| General Category | Uppercase Letter |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Left To Right |
| Decomposition Type | Font |
| Decomposition Mapping | "Q" U+0051 Latin Capital Letter Q |
Encodings
| HTML Decimal Encoding | ℚ |
| HTML Hex Encoding | ℚ |
| UTF-8 Encoding | 0xE2 0x84 0x9A |
| UTF-16 Encoding | 0x211A |
| UTF-32 Encoding | 0x0000211A |
| C/C++/Java Escape | \u211a |
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 | "q" U+0071 Latin Small Letter Q |
| NFKC Simple Casefold | "q" U+0071 Latin Small Letter Q |
| 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 |