GB/T 2312-1980 is a key officialcharacter set of thePeople's Republic of China, used forSimplified Chinese characters.GB2312 is the registered internet name forEUC-CN, which is its usual encoded form.GB refers to theGuobiao standards (国家标准), whereas theT suffix (推荐;tuījiàn; 'recommendation') denotes a non-mandatory standard.^[1]

GB/T 2312-1980 was originally a mandatory national standard designatedGB 2312-1980. However, following a National Standard Bulletin of thePeople's Republic of China in 2017, GB 2312 is no longer mandatory, and its standard code is modified toGB/T 2312-1980.^[2]GB/T 2312-1980 has been superseded byGBK andGB 18030, which include additional characters, butGB/T 2312 remains in widespread use as a subset of those encodings.

As of September 2022^[update], GB2312 is the second-most popular encoding served from China and territories (afterUTF-8), with 5.5% of web servers serving a page declaring it.^[3] Globally, GB2312 is declared on 0.1% of all web pages.^[4] However, all major web browsers decode GB2312-marked documents as if they were marked with the superset GBK encoding, except for Safari and Edge on the labelGB_2312.^[5]

There is an analogous character set known asGB/T 12345Code of Chinese ideogram set for information interchange supplementary set, which supplements GB/T 2312 withtraditional character forms by replacing simplified forms in their qūwèi code, and some extra 62 supplemental characters.^[6][7] GB-encoded fonts often come in pairs, one with the GB/T 2312 (simplified) character set and the other with the GB/T 12345 (traditional) character set. There exists more GB supplementary encoding sets that supplements GB/T 2312, including GB/T 7589Code of Chinese ideograms set forinformation interchange--The 2nd supplementary set and GB/T 7590Code of Chinese ideograms set forinformation interchange--The 4th supplementary set which provides additional [Variant Chinese characters|variant characters] in the sameqūwèi encoding format (later used in ISO-2022-CN), but has no relation with characters encoded in GB/T 2312.

While GB/T 2312 covers over 99.99% contemporary Chinese text usage,^[8] historical texts and many names remain out of scope. OldGB 2312 standard includes 6,763 Chinese characters (on two levels: the first is arranged by reading, the second byradical then number of strokes), along with symbols and punctuation, Japanesekana, theGreek andCyrillic alphabets,Zhuyin, and a double-byte set ofPinyin letters with tone marks. In later version GB/T 2312-1980, there are 7,445 letters.

Characters in GB/T 2312 are arranged in a 94×94 grid (as inISO 2022), and the two-byte code point of each character is expressed in theqūwèi (区位) form, which specifies a row (区;qū) and the position of the character within the row (cell;位;wèi). (This structure is the same as used by otherISO-2022-based nationalCJK character set standards; comparekuten.) For example, the character "外" (meaning: foreign) is located in row 45 position 66,^[9] thus itsqūwèi code is 45-66.

The rows (numbered from 1 to 94) contain characters as follows:

• 01–09, comprising punctuation and other special characters; alsoHiragana,Katakana,Greek,Cyrillic,Pinyin,Bopomofo
• 16–55, the first level ofChinese characters, arranged according toPinyin. (3755 characters).
• 56–87, the second level of Chinese characters, arranged according to radical and strokes. (3008 characters).

The rows 10–15 and 88–94 are unassigned.

For GB/T 2312-1980, it contains 682 signs and 6763 Chinese Characters.

EUC-CN is often used as thecharacter encoding (i.e. for external storage) in programs that deal with GB/T 2312, thus maintaining compatibility withASCII. Twobytes are used to represent every character not found inASCII. The value of the first byte is from0xA1–0xF7 (161–247), while the value of the second byte is from0xA1–0xFE (161–254). Since all of these ranges are beyond ASCII, like UTF-8, it is possible to check if a byte is part of a multi-byte construct when using EUC-CN, but not if a byte is first or last.

Compared toUTF-8, GB/T 2312 (whether native or encoded in EUC-CN) is more storage efficient: whileUTF-8 uses three bytes^[a] perCJK ideograph, GB/T 2312 only uses two. However, GB/T 2312 does not cover as many ideographs as Unicode does.

To map theqūwèi code points to EUC bytes, add 160 (0xA0) to both the row number (or qū, 区) and cell/column number (ten or wèi, 位). The result of addition to the row number of the code point will form the high byte, and the result of addition to the cell number of the code point will form the low byte.

For example, to encode the character "外" atqūwèi cell 45-66, the high byte will use the row number 45: 45+160=205=0xCD, and the low byte will come from the cell number 66: 66+160=226=0xE2. So, the full encoding is<CD E2>.^[10][11]

ISO-2022-CN is another encoding form of GB/T 2312, which is also the encoding specified in the official documentation. This encoding references theISO-2022 standard, which also uses two bytes to encode characters not found in ASCII. However, instead of using the extended region of ASCII, ISO-2022 uses the same byte range as ASCII: the value of the first byte is from0x21–0x77 (33–119), while the value of the second byte is from0x21–0x7E (33–126). As the byte range overlaps ASCII significantly, special characters are required to indicate whether a character is in the ASCII range or is part of the two-byte sequence of extended region, namely theShift Out and Shift In functions. This poses a risk for misencoding as improper handling of text can result in missing information.

To map theqūwèi code points to ISO-2022 bytes, add 32 (0x20) to both the row number (or qū, 区) and cell/column number (or wèi, 位). The result of addition to the row number of the code point will form the high byte, and the result of addition to the cell number of the code point will form the low byte similar to EUC encoding.

For example, to encode the character "外" atqūwèi cell 45-66, the high byte will use the row number 45: 45+32=77=0x4D, and the low byte will come from the cell number 66: 66+32=98=0x62. So, the full encoding is<4D 62>.^[11]

HZ is another encoding of GB/T 2312 that is used mostly forUsenet postings; characters are represented with the same byte pairs as in ISO-2022-CN, but the byte sequences denoting the beginning and end of a range of GB 2312 text differ.

In the tables below, where a pair of hexadecimal numbers is given for a prefix byte or a coding byte, the smaller (with the eighth bit unset or unavailable) is used when encoded over GL (0x21-0x7E), as inISO-2022-CN orHZ-GB-2312, and the larger (with the eighth bit set) is used in the more typical case of it being encoded over GR (0xA1-0xFE), as inEUC-CN,GBK orGB 18030.Qūwèi numbers are given in decimal.

When GB/T 2312 is encoded over GR, both bytes have the eighth bit set (i.e. are greater than 0x7F). GBK and GB 18030 also make use of two-byte codes in which only the first byte has the eighth bit set for extension purposes: such codes are outside of the GB/T 2312 plane, and are not tabulated here.

This chart details the overall layout of the main plane of the GB/T 2312 character set by lead byte. For lead bytes used for characters other thanhanzi, links are provided to charts on this page listing the characters encoded under that lead byte. For lead bytes used for hanzi, links are provided to the appropriate section ofWiktionary's hanzi index.

The following charts list the non-hanzi characters available in GB/T 2312, in GB/T 12345, and in double-byte region 1 ofGB 18030 (which roughly corresponds to the non-hanzi region of GB/T 2312). Notes are made where these differ, and whereGB 6345.1 andISO-IR-165 differ from these. Cross-references are made to articles on other CJK national character sets for comparison.

Unicode mappings of theinterpunct (Chinese:间隔点;lit. 'separator dot') andem dash (Chinese:破折号) in the subset ofGBK andGB 18030 corresponding to GB/T 2312 (U+00B7 ·MIDDLE DOT andU+2014 —EM DASH) differ from those which are listed in GB2312.TXT (U+30FB ・KATAKANA MIDDLE DOT andU+2015 ―HORIZONTAL BAR), which is a data file which was previously provided by theUnicode Consortium,^[13] although it has been designated as obsolete since August 2011^[14] and is no longer hosted as of September 2016.

As of 2015, Microsoft .Net Framework follows GB 18030 mappings when mapping those two characters in data labelledgb2312, whereasICU,^[15] iconv-1.14,^[16] php-5.6, ActivePerl-5.20, Java 1.7 and Python 3.4^[17] follow GB2312.TXT in response to thegb2312 label. Ruby 2.2 is compatible with both implementations; it internally converts the conflictive characters to the GB 18030 subset. TheW3C/WHATWG technical recommendation for use withHTML5 specifies a GBK encoding to be inferred for streams labelledgb2312, which in turn uses a GB18030 decoder.^[18]

Other differing mappings have been defined and used by individual vendors,^[13] including one fromApple.^[19]

This row contains punctuation, mathematical operators, and other symbols. The following table shows the GB 18030 mappings^[20] for these GB/T 2312 characters first, followed by any other documented mappings.

This row contains various types of list marker. Lowercase forms of the Roman numerals were not included in the original GB/T 2312^[21] nor in GB/T 12345,^[6] but are included in bothWindows code page 936^[22] andGB 18030.^[20] Aeuro sign was also added by GB 18030.^[20]

This row containsISO 646-CN (GB/T 1988-80), a national counterpart toASCII. Comparerow 3 of KS X 1001, which does the same withSouth Korea's ISO 646 version, androw 3 of JIS X 0208 andof KPS 9566, which include only the alphanumeric subset, but in the same layout. The following chart lists ISO 646-CN.

When used in an encoding allowing combination with ASCII such asEUC-CN (and its supersetGB 18030), these characters are usually implemented asfullwidth characters, hence mappings to theHalfwidth and Fullwidth Forms block are used as shown below.GB 6345.1 also handles this row as fullwidth, and adds the halfwidth forms (as above) as row 10.^[1] Apple mostly maps this row to fullwidth code points as below, but uses non-fullwidth mappings for the overline andyuan sign as above.^[19]

This set containsHiragana for writing theJapanese language.

Compare withrow 4 of JIS X 0208, which this row matches, and withrow 10 of KS X 1001 andof KPS 9566, which use the same layout, but in a different row.

This set containsKatakana for writing theJapanese language. However, theJapanese long vowel mark, which is used in katakana text and included in row 1 ofJIS X 0208, is not included in GB/T 2312, although it is added in GBK and GB 18030 outside of the main GB/T 2312 plane,^[24] at 0xA960.^[20]

Compare withrow 5 of JIS X 0208, which this row matches, and withrow 11 of KS X 1001 andof KPS 9566, which use the same layout, but in a different row.

This row contains basic support for the modernGreek alphabet, without diacritics or thefinal sigma.

The highlighted characters are presentation forms of punctuation marks for vertical writing, and are not included in GB/T 2312 proper, but are included in this row by GB/T 12345,^[1][6]Windows code page 936,^[22] Mac OS Simplified Chinese,^[19] and GB 18030.^[20] They are seen as "standard extensions to GB 2312".^[19] Conversely,ISO-IR-165 includes patternedsemigraphic characters in this row (mostly without exact counterparts in Unicode), colliding with the code positions used for the vertical extensions.^[25]

Compare withrow 6 of JIS X 0208, which this row matches when the vertical forms are not included, and withrow 6 of KPS 9566, which includes the same Greek letters in the same layout, but adds Roman numerals rather than vertical forms. Contrastrow 5 of KS X 1001, which offsets the Greek letters to include the Roman numerals first.

This set includes both cases of 33 letters from theCyrillic script, sufficient to write the modernRussian alphabet andBulgarian alphabet, although other forms of Cyrillic require additional letters.^[27]

Compare withrow 7 of JIS X 0208, which this row matches, and withrow 12 of KS X 1001 androw 5 of KPS 9566, which use the same layout but in different rows.

This row containsbopomofo andpinyin characters, excluding ASCII letters (which are in row 3). The highlighted characters are those which are not in the base GB 2312 set but are added byGB 6345.1,^[19] and also included in GB/T 12345,^[1][6]Windows code page 936,^[22] Mac OS Simplified Chinese^[19] and GB 18030.^[20] They are seen as "standard extensions to GB 2312".^[19]

GB 6345.1 treats the pinyin in this row as fullwidth, and includes halfwidth counterparts as row 11;^[1] GB 18030 does not do this.

GB 5007.1-8524×24BitmapFont Set of Chinese Characters for Information Exchange (Chinese:信息交换用汉字 24x24 点阵字模集) is the earliest font template based on GB/T 2312 that features corrections and extensions including:

• changing the glyph shape ofLatin alphabet "g"
• adding 6Hanyu Pinyin characters:ɑ,ḿ,ń,ň,ǹ,ɡ^{[note 1]}
• changed "鍾" to "锺"
• included 94 half-width glyphs in row 10 (half-width form of row 3, equivalent to GB 1988–80
• included half-width form of 32 Hanyu Pinyin characters from row 8 in row 11.

GB/T 2312 did not have corrections, but these corrections are included in font templates that are based on GB/T 2312 including GB/T 12345; its supersetsGBK andGB 18030 also included these corrections. GB/T 2312 is also used inISO-IR-165.

• GB 5007.1—198524×24 Dot matrix font set of Chinese ideograms for information interchange
• GB 5007.2—198524×24 Dot matrix font data set of Chinese ideograms for information interchange
• GB 5199.1—198515×16 Dot matrix font set of Chinese ideograms for information interchange
• GB 5199.2—198515×16 Dot matrix font data set of Chinese ideograms for information interchange
• GB 6345.1—198632×32 Dot matrix font set of Chinese ideograms for information interchange
• GB 6345.2—198632×32 Dot matrix font data set of Chinese ideograms for information interchange
• GB/T 12034—198932×32 Dot matrixFangsongti font set and data set of Chinese ideograms for information interchange
• GB/T 12035—198932×32 Dot matrixKaiti font set and data set of Chinese ideograms for information interchange
• GB/T 12036—198932×32 Dot matrixHeiti font set and data set of Chinese ideograms for information interchange
• GB/T 12037—198936×36 Dot matrixSongti font set and data set of Chinese ideograms for information interchange
• GB/T 12038—198936×36 Dot matrix Fangsongti font set and data set of Chinese ideograms for information interchange
• GB/T 12039—198936×36 Dot matrix Kaiti font set and data set of Chinese ideograms for information interchange
• GB/T 12040—198936×36 Dot matrix Heiti font set and data set of Chinese ideograms for information interchange
• GB/T 12041—198948×48 Dot matrix Songti font set and data set of Chinese ideograms for information interchange
• GB/T 12042—198948×48 Dot matrix Fangsongti font set and data set of Chinese ideograms for information interchange
• GB/T 12043—198948×48 Dot matrix Kaiti font set and data set of Chinese ideograms for information interchange
• GB/T 12044—198948×48 Dot matrix Heiti font set and data set of Chinese ideograms for information interchange
• GB/T 13443—1992128×128 Dot matrix kaitifont set and data set of Chinese ideograms for information interchange
• GB/T 13444—1992128×128 Dot matrix Fangsongti font set and data set of Chinese ideograms for information interchange
• GB/T 13445—1992256×256 Dot matrix Kaiti font set and data set of Chinese ideograms for information interchange
• GB/T 13446—1992256×256 Dot matrix Fangsongti font set and data set of Chinese ideograms for information interchange
• GB/T 13844—1992Vector Danxian Songti font set and data set of Chinese ideogram for graphics information interchange
• GB/T 13845—1992Vector Songti font set and data set of Chinese ideogram for graphics information interchange
• GB/T 13846—1992Vector Fangsongti font set and data set of Chinese ideogram for graphics information interchange
• GB/T 13847—1992Vector Kaiti font set and data set of Chinese ideogram for graphics information interchange
• GB/T 13848—1992Vector Heiti font set and data set of Chinese ideogram for graphics information interchange

• Guobiao code
• CJK characters
• Chinese character encoding
• Unicode
• Big5 – standard used in Taiwan and Hong Kong
• GB 18030, which has superseded GB/T 2312-1980
• GB/T 12345-1990, traditional counterpart of GB/T 2312-1980, superseded by GB18030

• Lunde, Ken (2009)."Chinese Character Set Standards—China".CJKV Information Processing (2nd ed.). O'Reilly.ISBN 978-0-596-51447-1.

• Graphical View of GB2312 in ICU's Converter Explorer
• Unicode to GB2312 or GBK table
• Chinese Character Codes
• Evolution of GBK and GB2312 into GB18030
• GB2312 Character Set for Chinese Characters
• Coded Chinese Graphic Character Set for Information Interchange ISO-IR 58
• C code generates 6763 basic characters with output
• GB2312-80 standard on China-Language.gov.cn

• Character sets
• Guobiao standards
• Encodings of Asian languages
• Chinese character encodings

• All articles with dead external links
• Articles with dead external links from January 2021
• Articles with permanently dead external links
• Articles with short description
• Short description is different from Wikidata
• Articles containing Chinese-language text
• Articles containing potentially dated statements from September 2022
• All articles containing potentially dated statements
• Articles containing simplified Chinese-language text