What rank corresponds to O-6?

The rank that corresponds to O-6 is Captain. In the U.S. Navy, ranks are categorized into pay grades, and O-6 is classified as the sixth officer rank within that system. A Captain in the Navy typically commands a significant vessel or is in charge of a major shore installation. The title of Captain does not refer to the military title of captain in general terms, such as in the context of small boats or civilian ships; instead, it denotes a specific rank ranking above Commander (O-5) and below Rear Admiral Lower Half (O-7). This hierarchy is essential for understanding the command structure and responsibilities assigned to various ranks within the Navy. The other ranks mentioned do not align with the O-6 classification.