| Name | Other Name | Family | Nativ Name | ISO6391 Code | ISO6392T Code | ISO6392B Code | ISO6393 Code | Notes |
|---|---|---|---|---|---|---|---|---|
| Javanese | Austronesian | ꦧꦱꦗꦮ; Basa Jawa | jv | jav | jav | jav | ||
| Japanese | Japonic | 日本語 (にほんご) | ja | jpn | jpn | jpn | ||
| Inuktitut | Eskimo–Aleut | ᐃᓄᒃᑎᑐᑦ | iu | iku | iku | iku + 2 | macrolanguage | |
| Italian | Indo-European | Italiano | it | ita | ita | ita | ||
| Icelandic | Indo-European | Íslenska | is | isl | ice | isl | ||
| Ido | Constructed | Ido | io | ido | ido | ido | constructed by De Beaufront; 1907; as variation of Esperanto | |
| Inupiaq | Eskimo–Aleut | Iñupiaq; Iñupiatun | ik | ipk | ipk | ipk + 2 | macrolanguage | |
| Igbo | Niger–Congo | Asụsụ Igbo | ig | ibo | ibo | ibo | ||
| Irish | Indo-European | Gaeilge | ga | gle | gle | gle | ||
| Finnish | Uralic | suomi; suomen kieli | fi | fin | fin | fin |