| Displacement | 1630t standard, 1833t surface, 2602t submerged |
|---|---|
| Length | 98.6m pp, 102.6m wl, 105.5m oa |
| Width | 8.25m |
| Draught | 4.60m |
| Machinery | 2-shaft diesel and electoric motor, 8000bhp surface, 1800shp submerged |
| Speed | 23.1kt surface, 8kt submerged |
| Armament | 6-53cm TT, 1-12cm/45cal gun, 2-25mm AA |
| Complement | 88 |
| Name | Plan | Builder | Laid down | Launch | Complete | ||
|---|---|---|---|---|---|---|---|
| I-176 (I-76) | FY1939 | Kure NYd | 1940. 6.22 | 1941. 6. 7 | 1942. 8. 4 | SS1 | 1944. 5.16 sunk (action, near Buka I.) [04.01S, 156.29E] 1944. 6.11 missing 1944. 7.10 disc |
| I-177 (I-77) | FY1939 | Kawasaki, Kobe | 1941. 3.10 | 1941.12.20 | 1942.12.28 | SS1 | 1944.10. 3 sunk (action, off Palau) [07.48N, 133.28E] 1944.11.18 missing 1945. 3. 1 disc |
| I-178 (I-78) | FY1939 | Mitsubishi, Kobe | 1941. 5.21 | 1942. 2.24 | 1942.12.26 | SS1 | 1943. 8. 4 missing (Solomons area) [15.35S, 166.17E] 1943. 9. 1 disc |
| I-179 | FY1939 | Kawasaki, Kobe | 1941. 8.21 | 1942. 7.16 | 1943. 6.18 | SS1 | 1943. 7.14 lost (accident, Iyo-nada) [33.40N, 132.40E] 1944. 9.15 disc 1957 refloat, BU |
| I-180 (I-80) | FY1939 | Yokosuka NYd | 1941. 4.17 | 1942. 2. 7 | 1943. 1.15 | SS1 | 1944. 5.20 missing (Aleutian area) [55.10N, 155.40W] 1944. 7.10 disc |
| I-181 (I-81) | FY1939 | Kure NYd | 1941.11.11 | 1942. 5. 2 | 1943. 5.24 | SS1 | 1944. 1.16 sunk (action, E of New Guinea) 1944. 3. 1 missing 1944. 4.30 disc |
| I-182 | FY1939 | Yokosuka NYd | 1941.11.10 | 1942. 5.30 | 1943. 5.24 | SS1 | 1943. 9. 3 sunk (action, near Espiritu Santo) [15.38S, 166.57E] 1943.10.22 missing 1943.12. 1 disc |
| I-183 | FY1939 | Kawasaki, Kobe | 1941.12.26 | 1943. 1.21 | 1943.10. 3 | SS1 | 1944. 4.28 sunk (torpedoed, S of Ashizuri point) [32.07N, 133.03E] 1944. 5.28 missing 1944. 8.10 disc |
| I-184 | FY1939 | Yokosuka NYd | 1942. 4. 1 | 1942.12.12 | 1943.10.15 | SS1 | 1944. 6.19 sunk (air attack, E of Saipan) [13.01N, 144.53E] 1944. 7.12 missing 1944. 8.10 disc |
| I-185 | FY1939 | Yokosuka NYd | 1942. 2. 9 | 1942. 9.16 | 1943. 9.23 | SS1 | 1944. 6.22 sunk (action, NW of Saipan) [15.50N, 147.08E] 1944. 7.12 missing 1944. 8.10 disc |