U+2151 · Other number
Vulgar Fraction One Ninth Symbol ⅑
⅑ is vulgar fraction one ninth, U+2151. Unicode records it as a compatibility form of 1⁄9 (fraction form). It was added in Unicode 5.2, and Unicode files it under Other number.
Codes & technical data
| Unicode | U+2151 | |
|---|---|---|
| HTML hex | ⅑ | |
| HTML decimal | ⅑ | |
| CSS | \2151 | |
| JavaScript | \u{2151} | |
| Python | \U00002151 | |
| Java / C# | \u2151 | |
| Rust | \u{2151} | |
| Swift | \u{2151} | |
| PHP | \u{2151} | |
| URL encoded | %E2%85%91 | |
| UTF-8 bytes | E2 85 91 | |
| UTF-16 bytes | 2151 | |
| Base64 | 4oWR | |
| Decimal | 8529 | |
| Decomposes to | 1⁄9 (fraction form) | |
| Numeric value | 1/9 | |
| Category | Other number (No) | |
| Introduced | Unicode 5.2 | |
Will ⅑ survive being pasted?
- Normalisation. No. Anything that applies NFKC — search indexes, usernames, domain names, programming identifiers — rewrites ⅑ as
1⁄9. Safe for display, not for storage. - Legacy encodings. ⅑ is Unicode-only — it has no Latin-1 equivalent, so a system stuck on an 8-bit encoding cannot represent it.
- Size. 3 bytes in UTF-8. Character-limited fields — SMS, bios, some form validators — usually count bytes, not characters.
Nearby in Number Forms
Roman numerals as single characters, and the vulgar fractions beyond the three Latin-1 supplies. A Roman numeral here is one character, not a run of letters, so Ⅷ and VIII sort and search differently.
How to type ⅑
| Windows | Type 2151 then press Alt+X |
|---|---|
| macOS | Press Ctrl+Cmd+Space, then search for “vulgar fraction one ninth” |
| Linux | Press Ctrl+Shift+U, type 2151, press Enter |
| HTML | ⅑ |
About Unicode’s Other number category
This is classified as a number that is not a plain digit — a fraction, a superscript figure, a circled or bracketed numeral. Software will not parse it as a number without being told to.
Frequently asked questions
- How do I type the ⅑ vulgar fraction one ninth symbol?
- On Windows, type 2151 and press Alt+X. On Linux press Ctrl+Shift+U then 2151. On any system the quickest route is the copy button on this page.
- What is the code for ⅑?
- Vulgar Fraction One Ninth is U+2151. In UTF-8 it takes 3 bytes. The table above lists every escape format.
- Will ⅑ survive being pasted anywhere?
- Not always. Vulgar Fraction One Ninth is a compatibility character: any system that applies Unicode NFKC normalisation — search indexes, usernames, identifiers — replaces it with 1⁄9. Use it for display, not where text is normalised.