String Unicode Converter Online

1. Definition of Basic Nouns:
   1. Unicode Character Set : An abstract 'big warehouse' that contains all the words, symbols, Emoji. It only defines' what characters are there 'and does not care about what these characters look like in the computer (that is a matter of fonts), nor does it care about how they are stored. For example, it includes A, 你, 😀 characters.
   2. Unicode Code Point :Assign a unique numerical number to each abstract character in the character set. This is a mathematical integer ranging from U+0000 to U+10FFFF (approximately 1.11 million positions). Usually represented in hexadecimal with a U+prefix. For example, the code point for character A is U+0041 (decimal 65). 你 code point is U+4F60 (decimal 20320). Emoji 😀 code point is U+1F600 (decimal 128512).
   3. Unicode Character Encoding : The specific implementation rules for converting "Code Points" (integers) into "Binary Byte Stream". Because computers only recognize 0 and 1. However, the size of the code points varies (some require 1 byte of storage, while others require 4 bytes), so there must be an algorithm to specify how to store them so that they can be accurately parsed back when read. Common encoding schemes (UTF family):
      1. UTF-32 : Fixed length. All code points are fixed and stored in 4 bytes. Simple and straightforward, but extremely wasteful of storage space.
      2. UTF-16 : Var length. Commonly used characters (BMP) use 2 bytes, and rare characters/Emoji use 4 bytes (i.e. surrogate pairs). JavaScript and Java use this encoding internally.
      3. UTF-8 : Var length. It uses 1~4 bytes and is compatible with ASCII (English occupies 1 byte). It is the most popular encoding (HTML, file default) on the global Internet.
   4. Visual comparison table:

      Char	Unicode Code Point	UTF-8 Encoding	UTF-16 Encoding	UTF-32 Encoding
      A	U+0041	41 (1 Byte)	0041 (2 Byte)	00000041 (4 Byte)
      你	U+4F60	E4 BD A0 (3 Byte)	4F60 (2 Byte)	00004F60 (4 Byte)
      😀	U+1F600	F0 9F 98 80 (4 Byte)	D83D DE00 (4 Byte, surrogate pair)	0001F600 (4 Byte)

2. Input Content : Enter the string to be converted or the Unicode code point escape format string.
3. Mode : Select the conversion mode for string to Unicode.
   Keep ASCII : Convert characters outside of ASCII to the corresponding Unicode escape format, while keeping ASCII characters unchanged.
   Keep Latin1 : Convert characters other than Latin1 to the corresponding Unicode escape format, while keeping Latin1 characters unchanged.
   No Keep : Convert all input characters to Unicode escape format.
4. Code Point format: Select the escape format for the Unicode code points used. This tool supports the following five formats:
   1. \uXXXX : \u+four hexadecimal digits. Unicode Code Points greater than 0xFFFF are represented using surrogate pairs. The Java programming language uses this format.
   2. \u{XXXXX} : Variable length code points can represent all Unicode code points through variable length hexadecimal digits. PHP and Rust programming languages use this format.
   3. \UXXXXXXXX : \U+eight hexadecimal digits can represent all Unicode Code Points.
   4. \uXXXX\u{XXXXX} : Code points less than or equal to 0xFFFF, in the format of \uXXXX. Code points greater than 0xFFFF in the format of \u{XXXXX}. JavaScript and Ruby programming languages use this format.
   5. \uXXXX\UXXXXXXXX : Code points less than or equal to 0xFFFF, in the format of \uXXXX. Code points greater than 0xFFFF in the format of \UXXXXXXXX. Python, C/C++, C #, and Go programming languages use this format.
5. Case : Is hexadecimal digit uppercase or lowercase when converting a string to Unicode escape characters.
6. String to Unicode : Convert the input string to Unicode escape format using the selected mode.
7. Unicode to String : Convert the input Unicode escape characters to regular strings.
8. Open : Open a UTF-8 encoded text file.
9. Download : Download the conversion result locally and encode the file as UTF-8.