U+2081 · Other number
Subscript One Symbol ₁
₁ is subscript one, and Unicode gives it the numeric value 1. It was added in Unicode 1.1, and Unicode files it under Other number.
Also known as
Unicode 1.0 called this character subscript digit one. The standard renamed it later, but documents, fonts and font-editing tools from that era still use the old name.
Codes & technical data
| Unicode | U+2081 | |
|---|---|---|
| HTML hex | ₁ | |
| HTML decimal | ₁ | |
| CSS | \2081 | |
| JavaScript | \u{2081} | |
| Python | \U00002081 | |
| Java / C# | \u2081 | |
| Rust | \u{2081} | |
| Swift | \u{2081} | |
| PHP | \u{2081} | |
| URL encoded | %E2%82%81 | |
| UTF-8 bytes | E2 82 81 | |
| UTF-16 bytes | 2081 | |
| Base64 | 4oKB | |
| Decimal | 8321 | |
| Decomposes to | 1 (sub form) | |
| Numeric value | 1 | |
| Category | Other number (No) | |
| Introduced | Unicode 1.1 | |
Will ₁ survive being pasted?
- Normalisation. No. Anything that applies NFKC — search indexes, usernames, domain names, programming identifiers — rewrites ₁ as
1. Safe for display, not for storage. - Legacy encodings. ₁ 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.
Other one characters
Unicode names 10 characters ending in “one”. They differ by direction, weight or decoration rather than by meaning.
Nearby in Superscripts and Subscripts
Raised and lowered digits and a handful of letters, as single characters rather than as formatting. Useful precisely where formatting is unavailable — filenames, usernames, plain-text fields — though the alphabet is incomplete and always has been.
How to type ₁
| Windows | Type 2081 then press Alt+X |
|---|---|
| macOS | Press Ctrl+Cmd+Space, then search for “subscript one” |
| Linux | Press Ctrl+Shift+U, type 2081, press Enter |
| HTML | ₁ |
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 ₁ subscript one symbol?
- On Windows, type 2081 and press Alt+X. On Linux press Ctrl+Shift+U then 2081. On any system the quickest route is the copy button on this page.
- What is the code for ₁?
- Subscript One is U+2081. In UTF-8 it takes 3 bytes. The table above lists every escape format.
- Will ₁ survive being pasted anywhere?
- Not always. Subscript One is a compatibility character: any system that applies Unicode NFKC normalisation — search indexes, usernames, identifiers — replaces it with 1. Use it for display, not where text is normalised.