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U+2205

EMPTY SET

General category
Math Symbol Sm
Unicode block
Mathematical Operators
Combining class
0
Bidirectional class
ON
Mirrored
No

U+2205 EMPTY SET is a Unicode 16.0.0 character in the Math Symbol category. It belongs to the Mathematical Operators block.

Encodings & representations

Choose the representation you need, then copy its value.

Code point

U+2205

Decimal value

8709

HTML decimal reference

∅

HTML hexadecimal reference

∅

HTML named reference

∅

UTF-8 bytes (hex)

E2 88 85

UTF-16 code units (hex)

2205

UTF-32 code unit (hex)

00002205

URL percent-encoded UTF-8

%E2%88%85

C# Unicode escape

\u2205

JavaScript Unicode escape

\u2205

JSON Unicode escape

\u2205

CSS Unicode escape (trailing space)

\2205
About these encodings
  • ASCII positions run from 0 to 127. Position cards show the decimal byte value followed by hexadecimal.
  • “Extended ASCII” is not a single encoding. ISO-8859-1 (Latin-1) and Windows-1252 are shown separately; they differ at bytes 128–159. Windows-1252 leaves five of those bytes undefined.
  • Legacy position cards appear only when the character has an exact mapping. For example, the euro sign is Windows-1252 byte 128 (0x80), but has no ASCII or Latin-1 position. A legacy byte is not necessarily the Unicode code point or its UTF-8 encoding.
  • Percent encoding lists every UTF-8 byte; URL-safe characters do not normally need encoding.
  • JSON escapes omit the surrounding quotes.
  • UTF code units are not byte-order-specific.
  • HTML parsers remap numeric references for U+0000 and some control characters, so these may not round-trip.