U+21A8 "↨" Up down Arrow with Base Unicode Character
Unicode Version 17.0
↨
U+21A8 "↨" Up down Arrow with Base is a typographic symbol depicting a vertical line with an upward pointing arrowhead at the top and a downward pointing arrowhead at the bottom, anchored by a short horizontal base line. It is officially categorized as an arrow symbol and is often used in technical diagrams, signage, or user interfaces to indicate bidirectional vertical movement or alignment, such as in elevator buttons, mechanical controls, or computational flowcharts where a stable reference point is implied. Its design distinguishes it from simpler bidirectional arrows by the base, which emphasizes a fixed origin or baseline for the two opposing directions.
General Properties
| Code Point | U+21A8 |
| Version Added | 1.1 |
| Name | Up down Arrow with Base |
| Block | Arrows |
| General Category | Other Symbol |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Other Neutral |
Encodings
| HTML Decimal Encoding | ↨ |
| HTML Hex Encoding | ↨ |
| UTF-8 Encoding | 0xE2 0x86 0xA8 |
| UTF-16 Encoding | 0x21A8 |
| UTF-32 Encoding | 0x000021A8 |
| C/C++/Java Escape | \u21a8 |
Unicode Properties
| NFC Quick Check | Yes |
| NFD Quick Check | Yes |
| NFKC Quick Check | Yes |
| NFKD Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Alphabetic |
| Script | Common |
| Script Extensions | Common |
| Indic Syllabic Category | Other |
| Pattern Syntax | Yes |
| Vertical Orientation | Rotated |
| Grapheme Base | Yes |
| Grapheme Cluster Break | Other |
| Word Break | Other |
| Sentence Break | Other |