Io has been divided into 15 quadrangles.[1]
| Name | Number | Latitude range | Longitude range | Namesake | Features |
|---|---|---|---|---|---|
| Ji1 | 65.5°–90° N | all | |||
| Ruwa Patera | Ji2 | 21.5°–65.5° N | 0°–90° W | Ruwa Patera | |
| Ji3 | 21.5°–65.5° N | 90°–180° W | Shango Patera, Amirani, Thor, Zamama | ||
| Ji4 | 21.5°–65.5° N | 180°–270° W | Thomagata Patera | ||
| Ji5 | 21.5°–65.5° N | 270°–360° W | Amaterasu Patera, Fuchi Patera, Kinich Ahau Patera, Manua Patera, Dazhbog Patera, Surt | ||
| Ji6 | 21.5° N – 21.5° S | 0°–72° W | Kanehekili Fluctus | ||
| Ji7 | 21.5° N – 21.5° S | 72°–144° W | Chaac-Camaxtli region, Monan Patera, Tawhaki Vallis, Ah Peku Patera, Gish Bar Patera, Maui Patera, Tawhaki Patera, Tupan Patera | ||
| Ji8 | 21.5° N – 21.5° S | 144°–216° W | Chaac-Camaxtli region, Prometheus | ||
| Ji9 | 21.5°N – 21.5° S | 216°–288° W | Asha Patera, Kami-Nari Patera, Reiden Patera, Pillan Patera, Pele | ||
| Ji10 | 21.5° N – 21.5° S | 288°–360° W | Loki Patera | ||
| Ji11 | 21.5°–65.5° S | 0°–90° W | Masubi | ||
| Ji12 | 21.5°–65.5° S | 90°–180° W | |||
| Ji13 | 21.5°–65.5° S | 180–270° W | Mithra Patera, Pyerun Patera, Svarog Patera, Egypt Mons, Danube Planum | ||
| Ji14 | 21.5°–65.5° S | 270–360° W | Babbar Patera, Viracocha Patera, Euboea Montes, Silpium Mons | ||
| Ji15 | 65.5°–90° S | all |