| 01 | ONIX audience codes | Using a code from List 28 | 6 | |
| 02 | Proprietary | As specified in <AudienceCodeTypeName> | 0 | |
| 03 | MPAA rating | Motion Picture Association of America rating applied to movies | 0 | |
| 04 | BBFC rating | British Board of Film Classification rating applied to movies | 0 | |
| 05 | FSK rating | German FSK (Freiwillige Selbstkontrolle der Filmwirtschaft) rating applied to movies | 1 | |
| 06 | BTLF audience code | French Canadian audience code list, used by BTLF for Memento | 4 | |
| 07 | Electre audience code | Audience code used by Electre (France) | 4 | |
| 08 | ANELE Tipo | Spain: educational audience and material type code of the Asociación Nacional de Editores de Libros y Material de Enseñanza | 5 | |
| 09 | AVI | Code list used to specify reading levels for children’s books, used in Flanders, and formerly in the Netherlands – see also code 18 | 7 | 11 |
| 10 | USK rating | German USK (Unterhaltungssoftware Selbstkontrolle) rating applied to video or computer games | 7 | |
| 11 | AWS | Audience code used in Flanders | 8 | |
| 12 | Schulform | Type of school: codelist formerly maintained by VdS Bildungsmedien eV, the German association of educational media publishers at http://www.bildungsmedien.de/service/onixlisten/schulform_onix_codelist29_value12_0408.pdf. Deprecated – use Thema educational purpose qualifier (eg 4Z-DE-BA – for German Elementary School) in <Subject> instead | 8 | 60 |
| 13 | Bundesland | School region: codelist maintained by VdS Bildungsmedien eV, the German association of educational media publishers, indicating where products are licensed to be used in schools. See http://www.bildungsmedien.de/service/onixlisten/bundesland_onix_codelist29_value13_0408.pdf. Deprecated | 8 | 59 |
| 14 | Ausbildungsberuf | Occupation: codelist for vocational training materials formerly maintained by VdS Bildungsmedien eV, the German association of educational media publishers at http://www.bildungsmedien.de/service/onixlisten/ausbildungsberufe_onix_codelist29_value14_0408.pdf. Deprecated – use Thema educational purpose qualifier (eg 4Z-DE-UH – for specific German professional/vocational qualifications and degrees) in <Subject> instead | 8 | 60 |
| 15 | Suomalainen kouluasteluokitus | Finnish school or college level | 8 | |
| 16 | CBG age guidance | UK Publishers Association, Children’s Book Group, coded indication of intended reader age, carried on book covers | 8 | |
| 17 | Nielsen Book audience code | Audience code used in Nielsen Book Services | 11 | |
| 18 | AVI (revised) | Code list used to specify reading levels for children’s books, used in the Netherlands – see also code 09 | 11 | |
| 19 | Lexile measure | Lexile measure (the Lexile measure in <AudienceCodeValue> may optionally be prefixed by the Lexile code). Examples might be ‘880L’, ‘AD0L’ or ‘HL600L’. Deprecated – use <Complexity> instead | 12 | 24 |
| 20 | Fry Readability score | Fry readability metric based on number of sentences and syllables per 100 words. Expressed as a number from 1 to 15 in <AudienceCodeValue>. Deprecated – use <Complexity> instead | 14 | 24 |
| 21 | Japanese Children’s audience code | Children’s audience code (対象読者), two-digit encoding of intended target readership from 0–2 years up to High School level | 18 | |
| 22 | ONIX Adult audience rating | Publisher’s rating indicating suitability for a particular adult audience, using a code from List 203. Should only be used when the ONIX Audience code indicates a general adult audience (code 01 from List 28) | 18 | 47 |
| 23 | Common European Framework of Reference for Language Learning (CEFR) | Codes A1 to C2 indicating standardised level of language learning or teaching material, from beginner to advanced, defined by the Council of Europe (see http://www.coe.int/lang-CEFR) | 19 | 41 |
| 24 | Korean Publication Ethics Commission rating | Rating used in Korea to control selling of books and e-books to minors. Current values are 0 (suitable for all) and 19 (only for sale to ages 19+). See http://www.kpec.or.kr/english/ | 21 | |
| 25 | IoE Book Band | UK Institute of Education Book Bands for Guided Reading scheme (see http://www.ioe.ac.uk/research/4664.html). <AudienceCodeValue> is a color, eg ‘Pink A’ or ‘Copper’. Deprecated – use <Complexity> instead | 23 | 24 |
| 26 | FSK Lehr-/Infoprogramm | Used for German videos/DVDs with educational or informative content; value for <AudienceCodeValue> must be either ‘Infoprogramm gemäß § 14 JuSchG’ or ‘Lehrprogramm gemäß § 14 JuSchG’ | 23 | |
| 27 | Intended audience language | Where this is different from the language of the text of the book recorded in <Language>. <AudienceCodeValue> should be a value from List 74 | 25 | |
| 28 | PEGI rating | Pan European Game Information rating used primarily for video games | 25 | |
| 29 | Gymnasieprogram | Code indicating the intended curriculum (eg Naturvetenskapsprogrammet, Estetica programmet) in Swedish higher secondary education | 28 | |
| 30 | ISCED 2011 | International Standard Classification of Education levels (2011), eg <AudienceCodeValue> 253 is ‘Lower secondary vocational education, level completion without direct access to upper secondary education’. Only for use in ONIX 3.0 or later. See http://uis.unesco.org/en/topic/international-standard-classification-education-isced | 55 | |