At 150,000 gross tons, Johan Castberg is the 1,463rd largest of the 84,014 vessels in this registry that report a tonnage. The median across that set is 5,994 GT, so this hull is about 25 times the typical vessel on record here. The largest measures 499,167 GT.
Among the 911 rig / offshore units held here, it ranks 11th by tonnage — larger than 99% of that group. Their median tonnage is 9,254 GT, and the largest tenth begin at 51,732 GT. The flag most often flown by this group is Liberia (179 ships). The yard that appears most often against it is Hanwha Ocean, with 27 hulls on record.
Johan Castberg was built in 2024, making it 2 years old. It is one of 116 hulls in this registry delivered that year, a cohort whose median tonnage is 25,985 GT; within it this ship is the 19th largest. Across the whole of the 2020s the registry holds 1,769 vessels, median 29,777 GT. The median build year across the entire registry is 1995.
The registry attributes 12 vessels to Seatrium Limited, with a median tonnage of 29,631 GT, delivered between 1997 and 2024. See the rest of that yard’s output.
At 313.0 m overall, Johan Castberg is 239.0 m longer than the 74.0 m median for rig / offshore units on record.
IMO numbers are issued in broadly chronological blocks. Within 500 either side of 9916575 this registry holds 5 other vessels, whose median build year is 2021 and which range from 2021 to 2024. That places this hull’s registration in the same part of the series, consistent with its recorded build year of 2024.
Its IMO number, 9916575, carries its own check digit. The first six digits are weighted seven down to two and summed — 9×7 + 9×6 + 1×5 + 6×4 + 5×3 + 7×2 = 175 — and the last digit of that total, 5, must equal the seventh digit, 5. It does, so this number is well formed.
