Starfleet Rank Index/Marines
Marshal & General Ranks
Field Marshal
The higest attainable rank in the Starfleet Marine Corps, Field Marshal is roughly equivalent to the rank of Fleet Admiral.
General
General is roughly equivalent to Starfleet's rank of Admiral.
Lieutenant General
Lieutenant General is roughly equivalent to Starfleet's rank of Vice Admiral.
Major General
Major General is akin to either Rear Admiral or Commodore (sometimes called "Rear Admiral, Lower Half") in Starfleet.
Brigadier General
Brigadier General is roughly equivalent to the rank of Fleet Captain.
Commissioned Marine Ranks
Colonel
A Colonel is equal to a Starfleet Captain in rank.
Lieutenant Colonel
A Lieutenant Colonel is comparable to a Commander in Starfleet.
Major
A Marine Major is equal to a Starfleet Lieutenant Commander.
Captain
A Marine Captain is equal in rank to a Starfleet Lieutenant.
First Lieutenant
File:M02-1Lt-Green.png First Lieutenant is roughly equivalent to the rank of Lieutenant Junior Grade in Starfleet's naval rank system.
Second Lieutenant
Second Lieutenant is SFMC's equivalent of the rank of Ensign.
Warrant Officer Marine Ranks
With regards to equivalent Starfleet Naval ranks, Warrant Officers are among the most self-explanatory. The only difference is the use of classes instead of grades when one reaches the rank of Chief Warrant Officer (CWO).