KOI8-U (RFC 2319) is an 8-bitcharacter encoding, designed to coverUkrainian, which uses aCyrillic alphabet. It is based onKOI8-R, which coversRussian andBulgarian, but replaces eight box drawing characters with four Ukrainian lettersҐ,Є,І, andЇ in both upper case and lower case.

KOI8-RU is closely related, but adds Ў forBelarusian. In both, the letter allocations match those inKOI8-E, except for Ґ which is added toKOI8-F.

InMicrosoft Windows, KOI8-U is assigned the code page number 21866. InIBM, KOI8-U is assigned code page/CCSID 1168.^[1][2][3]

KOI8 remains much more commonly used thanISO 8859-5, which never really caught on.^{[citation needed]} Another common Cyrillic character encoding isWindows-1251. In the future, both may eventually give way toUnicode.

KOI8 stands forKod Obmena Informatsiey, 8 bit (Russian:Код Обмена Информацией, 8 бит) which means "Code for Information Exchange, 8 bit".

The KOI8 character sets have the property that the Cyrillic letters are in pseudo-Latin alphabetic order rather than Cyrillic alphabetical order as in ISO 8859-5. This has the useful effect that if the eighth bit is stripped and the text is presented in any character set based on ASCII including the KOI8 sets themselves, the text is still reasonably human readable as a case-reversed transliteration. For instance, the "KOI" acronym "Код Обмена Информацией" becomeskOD oBMENA iNFORMACIEJ.

The following table shows the KOI8-U encoding.^[1][4] Each character is shown with its equivalentUnicode code point.

Although RFC 2319 says that character 0x95 should be U+2219 (∙), it may also be U+2022 (•) to match the bullet character inWindows-1251.

Some references have a typo and incorrectly state that character 0xB4 is U+0403, rather than the correct U+0404. This typo is present in Appendix A of RFC 2319 (but the table in the main text of the RFC gives the correct mapping).

• KOI character encodings
• Ukrainian alphabet

• Flohr, Guido (2016) [2006]."Locale::RecodeData::KOI8_U - Conversion routines for KOI8-U".CPAN libintl-perl. 1.1.Archived from the original on 2017-01-15. Retrieved2017-01-15.
• RFC 2319
• "KOI8-U (RFC 2319)".Kermit.Columbia University. Retrieved2020-06-24.
• Leishner, Mark (2008) [1999-12-20]."KOI8-U Belorussian/Ukrainian Cyrillic to Unicode 2.1 mapping table - Based on RFC 2319". Department of Mathematical Sciences, New Mexico State University.Archived from the original on 2017-02-19. Retrieved2017-02-19.
• Kornai, Andras; Birnbaum, David J.; da Cruz, Frank; Davis, Bur; Fowler, George; Paine, Richard B.; Paperno, Slava; Simonsen, Keld J.; Thobe, Glenn E.; Vulis, Dimitri; van Wingen, Johan W. (1993-03-13)."CYRILLIC ENCODING FAQ Version 1.3". 1.3.Archived from the original on 2017-02-18. Retrieved2020-06-24.

• Czyborra, Roman (1998-11-30) [1998-05-25]."The Cyrillic Charset Soup".Archived from the original on 2016-12-03. Retrieved2016-12-03.
• Hohlov, Yu. E."Cyrillic Information Representation in Electronic Form - Character Set (Code Page) Tables".Archived from the original on 2016-12-05. Retrieved2016-12-05.
• Nechayev, Valentin (2013) [2001]."Review of 8-bit Cyrillic encodings universe".Archived from the original on 2016-12-05. Retrieved2016-12-05.
• https://web.archive.org/web/20050206230944/http://www.net.ua/KOI8-U/

• Character sets

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