The international standard ISO 233 establishes a system for romanization of Arabic script. It was supplemented by ISO 233-2 in 1993 which is specific for Arabic language.

1984 edition

The table below shows the consonants for the Arabic language.

ISO 233-2:1993

ISO 233-2:1993 is an ISO schema for the simplified transliteration of Arabic characters into Roman characters and is dedicated to "Arabic language – Simplified transliteration". This transliteration system was adopted as an amendment to ISO 233:1984. It is used mainly in library context, and was introduced because ISO 233 was not meeting the indexing purposes, which are essential for the consistency of library catalogs. According to ISO 233-2(1993), Arabic words are vocalized prior to romanization. ISO 233-2 is used in French libraries and in North African libraries, and is recommended by ISSN for establishing key titles when cataloguing serials.

ISO 233-3:1999

ISO 233-3:1999 is dedicated to "Persian language – Simplified transliteration".

ISO/R 233:1961

ISO/R 233 is an earlier standard that has been withdrawn.