U+222C "∬" Double Integral Unicode Character
Unicode Version 17.0
∬
U+222C "∬" Double Integral is a mathematical symbol used to denote the integration of a function over a two-dimensional region, such as a surface or area. It represents the application of two successive single integral operations, commonly employed in calculus, physics, and engineering contexts to compute quantities like flux, volume under a surface, or surface integrals across a given plane. Unlike a single integral symbol, the double integral indicates that the integration is performed with respect to two variables, often visualized as summing infinitesimal elements across a 2D domain.
General Properties
| Code Point | U+222C |
| Version Added | 1.1 |
| Name | Double Integral |
| Block | Mathematical Operators |
| General Category | Math Symbol |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Other Neutral |
| Mirrored | Yes |
| Decomposition Type | Compat |
| Decomposition Mapping | "∫" U+222B Integral "∫" U+222B Integral |
Encodings
| HTML Decimal Encoding | ∬ |
| HTML Hex Encoding | ∬ |
| UTF-8 Encoding | 0xE2 0x88 0xAC |
| UTF-16 Encoding | 0x222C |
| UTF-32 Encoding | 0x0000222C |
| C/C++/Java Escape | \u222c |
Unicode Properties
| NFC Quick Check | Yes |
| NFD Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Ambiguous (Alphabetic or Ideographic) |
| East Asian Width | Ambiguous |
| Changes When NFKC Casefolded | Yes |
| NFKC Casefold | "∫" U+222B Integral "∫" U+222B Integral |
| NFKC Simple Casefold | "∫" U+222B Integral "∫" U+222B Integral |
| Script | Common |
| Script Extensions | Common |
| Indic Syllabic Category | Other |
| Pattern Syntax | Yes |
| Math | Yes |
| Vertical Orientation | Rotated |
| Grapheme Base | Yes |
| Grapheme Cluster Break | Other |
| Word Break | Other |
| Sentence Break | Other |