U+3390 "㎐" Square Hz Unicode Character
Unicode Version 17.0
㎐
U+3390 "㎐" Square Hz is a precomposed CJK compatibility ideograph that represents the unit of frequency "hertz" in a square format, specifically designed for efficient display in East Asian text environments where space is limited. It encodes the Latin letter "H" and "z" combined into a single glyph, matching the appearance of "Hz" enclosed within a square shape to fit neatly alongside other squared unit symbols like "㎏" (kilogram) or "㎝" (centimeter). Although it is classified under the CJK Compatibility block, its primary purpose is to maintain visual consistency in vertical writing and grid layouts, and it corresponds to the standard unit hertz, which measures cycles per second in physics and engineering contexts.
General Properties
| Code Point | U+3390 |
| Version Added | 1.1 |
| Name | Square Hz |
| Unicode 1.0 Name | Squared Hz |
| Block | CJK Compatibility |
| General Category | Other Symbol |
| Canonical Combining Class | Not Reordered |
| Bidirectional Class | Left To Right |
| Decomposition Type | Square |
| Decomposition Mapping | "H" U+0048 Latin Capital Letter H "z" U+007A Latin Small Letter Z |
Encodings
| HTML Decimal Encoding | ㎐ |
| HTML Hex Encoding | ㎐ |
| UTF-8 Encoding | 0xE3 0x8E 0x90 |
| UTF-16 Encoding | 0x3390 |
| UTF-32 Encoding | 0x00003390 |
| C/C++/Java Escape | \u3390 |
Unicode Properties
| NFC Quick Check | Yes |
| NFD Quick Check | Yes |
| Numeric Type | None |
| Numeric Value | NaN |
| Line Break | Ideographic |
| East Asian Width | Wide |
| Changes When NFKC Casefolded | Yes |
| NFKC Casefold | "h" U+0068 Latin Small Letter H "z" U+007A Latin Small Letter Z |
| NFKC Simple Casefold | "h" U+0068 Latin Small Letter H "z" U+007A Latin Small Letter Z |
| Script | Common |
| Script Extensions | Common |
| Indic Syllabic Category | Other |
| Vertical Orientation | Upright |
| Grapheme Base | Yes |
| Grapheme Cluster Break | Other |
| Word Break | Other |
| Sentence Break | Other |