0x00010FFFF

0x00010FFFF is the hexadecimal representation of the Unicode code point U+10FFFF. This code point is the highest value defined by the Unicode standard and marks the upper limit of the Unicode code space. It lies in the Supplementary Multilingual Plane (SMP), the first supplementary plane beyond the Basic Multilingual Plane.

U+10FFFF is considered a noncharacter under the Unicode specification. Noncharacters are code points that are permanently reserved and not intended to be assigned to characters for interchange, though they are valid scalar values. As such, U+10FFFF is not a character in the usual sense, and many systems purposefully avoid using it for text data.

Encoding and representations: In UTF-8, U+10FFFF is encoded as the four-byte sequence F0 90 8F BF. In UTF-16, it is encoded using a surrogate pair: 0xDBFF 0xDFFF. In UTF-32, it is represented directly as 0x00010FFFF. These encodings reflect the different internal representations used by text processing systems.

Usage: The code point is frequently cited as the upper bound of Unicode code points and is sometimes used in boundary testing, validation routines, and discussions of encoding limits. It is not assigned to a character and software libraries often handle it specially to avoid treating it as ordinary text.