U+203F · Connector punctuation
Undertie Symbol ‿
‿ is undertie, U+203F. Unicode also records it as “Greek enotikon”. It was added in Unicode 1.1, and Unicode files it under Connector punctuation.
Also known as
- Greek enotikon
Codes & technical data
| Unicode | U+203F | |
|---|---|---|
| HTML hex | ‿ | |
| HTML decimal | ‿ | |
| CSS | \203F | |
| JavaScript | \u{203F} | |
| Python | \U0000203F | |
| Java / C# | \u203F | |
| Rust | \u{203f} | |
| Swift | \u{203F} | |
| PHP | \u{203F} | |
| URL encoded | %E2%80%BF | |
| UTF-8 bytes | E2 80 BF | |
| UTF-16 bytes | 203F | |
| Base64 | 4oC/ | |
| Decimal | 8255 | |
| Category | Connector punctuation (Pc) | |
| Introduced | Unicode 1.1 | |
Will ‿ survive being pasted?
- Normalisation. Yes. ‿ is unchanged by NFKC, so it survives normalising systems intact.
- Legacy encodings. ‿ 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.
Unicode cross-references
The standard points readers of ‿ at these characters — usually because they look alike, or because one is the correct choice where the other is often used by mistake.
Nearby in General Punctuation
The typographic marks that word processors quietly substitute for their ASCII lookalikes — real quotation marks, en and em dashes, the ellipsis. It also holds the invisible characters: zero-width spaces, joiners and directional marks that do work without drawing anything.
How to type ‿
| Windows | Type 203F then press Alt+X |
|---|---|
| macOS | Press Ctrl+Cmd+Space, then search for “undertie” |
| Linux | Press Ctrl+Shift+U, type 203f, press Enter |
| HTML | ‿ |
About Unicode’s Connector punctuation category
This is connector punctuation — it joins words rather than separating them, which is why programming languages usually allow it inside identifiers where a hyphen is not allowed.
Frequently asked questions
- How do I type the ‿ undertie symbol?
- On Windows, type 203F and press Alt+X. On Linux press Ctrl+Shift+U then 203f. On any system the quickest route is the copy button on this page.
- What is the code for ‿?
- Undertie is U+203F. In UTF-8 it takes 3 bytes. The table above lists every escape format.
- What kind of character is ‿?
- Undertie is filed under Connector punctuation in the General Punctuation block, and was introduced in Unicode 1.1. This is connector punctuation — it joins words rather than separating them, which is why programming languages usually allow it inside identifiers where a hyphen is not allowed.