Predefined Constants
Basics of Japanese multi-byte encodings
Multibyte String
PHP Manual

# Summaries of supported encodings

Summaries of supported encodings
Name in the IANA character set registry:ISO-10646-UCS-4
Underlying character set:ISO 10646
Description: The Universal Character Set with 31-bit code space, standardized as UCS-4 by ISO/IEC 10646. It is kept synchronized with the latest version of the Unicode code map.
Additional note: If this name is used in the encoding conversion facility, the converter attempts to identify by the preceding BOM (byte order mark)in which endian the subsequent bytes are represented.
Name in the IANA character set registry:ISO-10646-UCS-4
Underlying character set:UCS-4
Description: See above.
Additional note: In contrast to UCS-4, strings are always assumed to be in big endian form.
Name in the IANA character set registry:ISO-10646-UCS-4
Underlying character set:UCS-4
Description: See above.
Additional note: In contrast to UCS-4, strings are always assumed to be in little endian form.
Name in the IANA character set registry:ISO-10646-UCS-2
Underlying character set:UCS-2
Description: The Universal Character Set with 16-bit code space, standardized as UCS-2 by ISO/IEC 10646. It is kept synchronized with the latest version of the unicode code map.
Additional note: If this name is used in the encoding conversion facility, the converter attempts to identify by the preceding BOM (byte order mark)in which endian the subsequent bytes are represented.
Name in the IANA character set registry:ISO-10646-UCS-2
Underlying character set:UCS-2
Description: See above.
Additional note: In contrast to UCS-2, strings are always assumed to be in big endian form.
Name in the IANA character set registry:ISO-10646-UCS-2
Underlying character set:UCS-2
Description: See above.
Additional note: In contrast to UCS-2, strings are always assumed to be in little endian form.
Name in the IANA character set registry:UTF-32
Underlying character set:Unicode
Description: Unicode Transformation Format of 32-bit unit width, whose encoding space refers to the Unicode's codeset standard. This encoding scheme wasn't identical to UCS-4 because the code space of Unicode were limited to a 21-bit value.
Additional note: If this name is used in the encoding conversion facility, the converter attempts to identify by the preceding BOM (byte order mark)in which endian the subsequent bytes are represented.
Name in the IANA character set registry:UTF-32BE
Underlying character set:Unicode
Description:See above
Additional note: In contrast to UTF-32, strings are always assumed to be in big endian form.
Name in the IANA character set registry:UTF-32LE
Underlying character set:Unicode
Description:See above
Additional note: In contrast to UTF-32, strings are always assumed to be in little endian form.
Name in the IANA character set registry:UTF-16
Underlying character set:Unicode
Description: Unicode Transformation Format of 16-bit unit width. It's worth a note that UTF-16 is no longer the same specification as UCS-2 because the surrogate mechanism has been introduced since Unicode 2.0 and UTF-16 now refers to a 21-bit code space.
Additional note: If this name is used in the encoding conversion facility, the converter attempts to identify by the preceding BOM (byte order mark)in which endian the subsequent bytes are represented.
Name in the IANA character set registry:UTF-16BE
Underlying character set:Unicode
Description: See above.
Additional note: In contrast to UTF-16, strings are always assumed to be in big endian form.
Name in the IANA character set registry:UTF-16LE
Underlying character set:Unicode
Description: See above.
Additional note: In contrast to UTF-16, strings are always assumed to be in little endian form.
Name in the IANA character set registry:UTF-8
Underlying character set:Unicode / UCS
Description: Unicode Transformation Format of 8-bit unit width.
Additional note:none
Name in the IANA character set registry:UTF-7
Underlying character set:Unicode
Description: A mail-safe transformation format of Unicode, specified in » RFC2152.
Additional note:none
Name in the IANA character set registry:(none)
Underlying character set:Unicode
Description: A variant of UTF-7 which is specialized for use in the » IMAP protocol.
Additional note:none
Name in the IANA character set registry: US-ASCII (preferred MIME name) / iso-ir-6 / ANSI_X3.4-1986 / ISO_646.irv:1991 / ASCII / ISO646-US / us / IBM367 / CP367 / csASCII
Underlying character set:ASCII / ISO 646
Description: American Standard Code for Information Interchange is a commonly-used 7-bit encoding. Also standardized as an international standard, ISO 646.
Additional note:(none)
Name in the IANA character set registry: EUC-JP (preferred MIME name) / Extended_UNIX_Code_Packed_Format_for_Japanese / csEUCPkdFmtJapanese
Underlying character set: Compound of US-ASCII / JIS X0201:1997 (hankaku kana part) / JIS X0208:1990 / JIS X0212:1990
Description: As you see the name is derived from an abbreviation of Extended UNIX Code Packed Format for Japanese, this encoding is mostly used on UNIX or alike platforms. The original encoding scheme, Extended UNIX Code, is designed on the basis of ISO 2022.
Additional note: The character set referred to by EUC-JP is different to IBM932 / CP932, which are used by OS/2® and Microsoft® Windows®. For information interchange with those platforms, use EUCJP-WIN instead.
Name in the IANA character set registry:Shift_JIS (preferred MIME name) / MS_Kanji / csShift_JIS
Underlying character set:Compound of JIS X0201:1997 / JIS X0208:1997
Description: Shift_JIS was developed in early 80's, at the time personal Japanese word processors were brought into the market, in order to maintain compatiblities with the legacy encoding scheme JIS X 0201:1976. According to the IANA definition the codeset of Shift_JIS is slightly different to IBM932 / CP932. However, the names "SJIS" / "Shift_JIS" are often wrongly used to refer to these codesets.
Additional note:For the CP932 codemap, use SJIS-WIN instead.
Name in the IANA character set registry:(none)
Underlying character set: Compound of JIS X0201:1997 / JIS X0208:1997 / IBM extensions / NEC extensions
Description: While this "encoding" uses the same encoding scheme as EUC-JP, the underlying character set is different. That is, some code points map to different characters than EUC-JP.
Additional note:none
Name in the IANA character set registry:Windows-31J / csWindows31J
Underlying character set: Compound of JIS X0201:1997 / JIS X0208:1997 / IBM extensions / NEC extensions
Description: While this "encoding" uses the same encoding scheme as Shift_JIS, the underlying character set is different. That means some code points map to different characters than Shift_JIS.
Additional note:(none)
Name in the IANA character set registry:ISO-2022-JP (preferred MIME name) / csISO2022JP
Underlying character set: US-ASCII / JIS X0201:1976 / JIS X0208:1978 / JIS X0208:1983
Description:» RFC1468
Additional note:(none)
Name in the IANA character set registry:JIS
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Name in the IANA character set registry:ISO-8859-1
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Name in the IANA character set registry:ISO-8859-2
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Name in the IANA character set registry:ISO-8859-3
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Name in the IANA character set registry:ISO-8859-4
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Name in the IANA character set registry:ISO-8859-5
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Name in the IANA character set registry:ISO-8859-6
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Name in the IANA character set registry:ISO-8859-7
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Name in the IANA character set registry:ISO-8859-8
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Name in the IANA character set registry:ISO-8859-9
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Name in the IANA character set registry:ISO-8859-10
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Name in the IANA character set registry:ISO-8859-13
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Name in the IANA character set registry:ISO-8859-14
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Name in the IANA character set registry:ISO-8859-15
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Name in the IANA character set registry:byte2be
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Name in the IANA character set registry:byte2le
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Name in the IANA character set registry:byte4be
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Name in the IANA character set registry:byte4le
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Name in the IANA character set registry:BASE64
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Name in the IANA character set registry:HTML-ENTITIES
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Name in the IANA character set registry:7bit
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Name in the IANA character set registry:8bit
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Name in the IANA character set registry:EUC-CN
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Name in the IANA character set registry:CP936
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Name in the IANA character set registry:HZ
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Name in the IANA character set registry:EUC-TW
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Name in the IANA character set registry:CP950
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Name in the IANA character set registry:BIG-5
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Name in the IANA character set registry:EUC-KR
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Name in the IANA character set registry:UHC (CP949)
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Name in the IANA character set registry:ISO-2022-KR
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Name in the IANA character set registry:Windows-1251 (CP1251)
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Name in the IANA character set registry:Windows-1252 (CP1252)
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Name in the IANA character set registry:CP866 (IBM866)
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Name in the IANA character set registry:KOI8-R
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Predefined Constants
Basics of Japanese multi-byte encodings
Multibyte String
PHP Manual