Mathematical symbol Not Element Of
About this character
The character ∉ carries the official Unicode name “Mathematical symbol Not Element Of” and the code point U+2209, which is 8713 in decimal. It belongs to the Mathematical Operators block (U+2200–U+22FF), which gathers the operators, quantifiers and relations of algebra, logic and set theory.
In memory, ∉ takes 3 bytes in UTF-8 (0xE2 0x88 0x89) and 1 in UTF-16 (0x2209). That difference is why badly configured forms or databases garble this character: they assume one byte per character.
How to type ∉
| System | What to do |
|---|---|
| Windows | In Word or WordPad, type 2209 and press Alt + X to turn the code into the character. |
| macOS | On a Mac, open the Character Viewer with Ctrl + ⌘ + Space and search for “Mathematical symbol Not Element Of”. |
| Linux | On Linux (GTK), type Ctrl + ⇧ + U, 2209 then press Enter. |
| HTML / Web | In an HTML page, write ∉. Use \2209 in CSS, \u2209 in JavaScript and \u2209 in Python. |
| On this site | The simplest route is the Copy button above: the character goes straight to your clipboard, ready to paste anywhere. |
Keyboards that include ∉
This character sits directly on the following ClavierVirtuel layouts, where you can click it with the mouse:
Codes and encodings
| Property | Value |
|---|---|
| Code point | U+2209 |
| Unicode block | Mathematical Operators (U+2200–U+22FF) |
| Decimal | 8713 |
| Hexadecimal | 0x2209 |
| Octal | 021011 |
| Binary | 10001000001001 |
| UTF-8 bytes | 0xE2 0x88 0x89 |
| UTF-16 units | 0x2209 |
| Named HTML entity | ∉ |
| Decimal HTML entity | ∉ |
| Hex HTML entity | ∉ |
| CSS escape | \2209 |
| JavaScript escape | \u2209 |
| Python escape | \u2209 |
| URL encoding | %E2%88%89 |
Frequently asked questions
What is the Unicode code for ∉?
Its code point is U+2209, which is 8713 in decimal and 021011 in octal. In HTML you can write it as ∉ or ∉.
Why does ∉ show up as a box or a question mark?
An empty box means the font has no glyph for U+2209. The character is still in the text: switching to a font that covers the block (Noto, DejaVu or Segoe UI Symbol) makes it appear.
Can I use ∉ in a filename, a URL or a password?
In a URL it must be encoded as %E2%88%89. Modern filesystems accept it, though it is still risky when moving files between systems. For passwords, some forms reject non-ASCII characters outright.