| # | Island | Area (km²) | Notes | % Correct |
|---|---|---|---|---|
| 2 | Hokkaidō 北海道 | 77,982 | 95%
| |
| 1 | Honshū 本州 | 227,938 | 95%
| |
| 3 | Kyūshū 九州 | 36,782 | 89%
| |
| 7 | Okinawa 沖縄本島 | 1,208 | Okinawa | 85%
|
| 4 | Shikoku 四国 | 18,296 | 85%
| |
| 10 | Tsushima 対馬 | 696 | Nagasaki | 55%
|
| 8 | Sado 佐渡島 | 855 | Niigata | 54%
|
| 11 | Awaji 淡路島 | 592 | Hyogo | 52%
|
| 9 | Amami Ōshima 奄美大島 | 712 | Amami Islands, Kagoshima | 44%
|
| 13 | Yakushima 屋久島 | 504 | Ōsumi Islands, Kagoshima | 43%
|
| 5 | Etorofu 択捉島 (Iturup) | 3,167 | administered by Russia | 41%
|
| 6 | Kunashiri 国後島 (Kunashir) | 1,489 | administered by Russia | 40%
|
| 14 | Tanegashima 種子島 | 444 | Ōsumi Islands, Kagoshima | 37%
|
| 18 | Shikotan 色丹島 (Shikotan) | 248 | administered by Russia | 29%
|
| 16 | Iriomote 西表島 | 290 | Yaeyama Islands, Okinawa | 19%
|
| 15 | Fukue 福江島 | 326 | Gotō Islands, Nagasaki | 18%
|
| 12 | Shimoshima 下島 | 575 | Amakusa Islands, Kumamoto | 10%
|
| 19 | Dōgo 島後 | 242 | Oki Islands, Shimane | 8%
|
| 20 | Kamishima 上島 | 226 | Amakusa Islands, Kumamoto | 8%
|
| 17 | Tokunoshima 徳之島 | 248 | Amami Isnalds, Kagoshima | 5%
|