Overview
ISO 9:1995 - "Information and documentation - Transliteration of Cyrillic characters into Latin characters - Slavic and non‑Slavic languages" is the second edition (1995) international standard that defines a strict, univocal and reversible system for transliterating Cyrillic script into Latin characters. It cancels and replaces ISO 9:1986. The standard is intended for automatic transmission and reconstitution of written messages by humans or machines and prioritizes unambiguous character‑by‑character mapping over phonetic or aesthetic considerations.
Key topics and technical requirements
- Stringent transliteration principle: transliteration must be univocal and entirely reversible so the original Cyrillic graphism can be reconstructed.
- Character‑by‑character mapping: each Cyrillic character is rendered by a single Latin character when possible; where the Latin set is smaller, digraphs or diacritical marks are used.
- Three conversion levels:
- Stringent transliteration - fully reversible; required for international exchange.
- Simplified conversion - allowed where technical constraints (e.g., machines not supporting diacritics) exist.
- Popular conversion - for media/press use where phonetic or local conventions dominate.
- Defined tables:
- Tables 1 and 2 cover Slavic Cyrillic characters (Bulgarian, Russian, Ukrainian, Serbian/Croatian, Macedonian, etc.).
- Table 3 provides mappings for Cyrillic characters used in non‑Slavic languages and lists 118 single or diacritic‑carrying characters in Cyrillic alphabetical order.
- Retransliteration: rules for converting Latin transliterations back into Cyrillic.
- Diacritical signs: diacritics used in the tables are drawn from the code table of ISO 5426 (see Annex A/B).
- Scope for national variants: countries may adopt compatible national standards provided they remain compatible with ISO 9’s univocal goals.
- Non‑phonetic approach: mappings ignore pronunciation and national orthographic aesthetics to maintain reversibility.
Applications
ISO 9:1995 is practical for any context requiring precise, machine‑readable and reversible Cyrillic-to‑Latin conversion:
- Library cataloguing, bibliographies, indexes and metadata standardization
- Archival digitization and document interchange
- Geographic names (toponymy) and cartography data exchange
- Multilingual databases, search engines and information retrieval systems
- Publishers, academic works and ISO/standards documentation
- Software development for romanization, data migration and localization
Who should use it
- Librarians, cataloguers and archivists
- Standards bodies and documentation specialists
- Software engineers, database administrators and GIS specialists
- Publishers, translators and researchers working with Cyrillic texts
Related standards
- ISO 5426 - code table referenced for diacritical signs used in ISO 9
- Work developed under ISO/TC 46, SC 2 (Conversion of written languages)
Using ISO 9:1995 ensures consistent, reversible romanization of Cyrillic script for reliable international information exchange, indexing and automated processing.