We’ve detected that you are using an outdated browser. This will prevent you from accessing certain features. Update browser

Carbon Intensity Indicator

Are you ready for CII?


The Carbon Intensity Indicator (CII) is a rating system for ships that the International Maritime Organization (IMO) developed. This will be a mandatory measure under MARPOL Annex VI, which came into force on the 1st January 2023.

The measure will impact all cargo, RoPax and cruise vessels above 5,000 gross tonnage (GT) and trading internationally.

The CII determines the annual reduction factor needed to continuously improve the ship's operational carbon intensity within a specific rating level. The actual annual operational CII achieved will need to be documented and verified against the required annual operational CII.

This will then enable the operational carbon intensity rating to be determined on a scale of A, B, C, D or E, indicating a major superior, minor superior, moderate, minor inferior, or inferior performance level. The performance level will need to be recorded in the ship's Ship Energy Efficiency Management Plan (SEEMP). A ship rated D or E for three consecutive years will need to submit a corrective action plan to show how the required index rating (C or above) will be obtained.

This short-term measure aims to achieve the carbon intensity reduction aims of the IMO's initial GHG emissions strategy.


Calculate your CII rating

Use our calculator to review your vessel’s Carbon Intensity Indicator rating (A to E).

Use our calculator
Over the shoulder view of a man interacting on a laptop with the EEXI e-training.

eLearning - EEXI and CII Regulation Awareness.

This eLearning course will help delegates navigate the regulations and fully prepare for the requirements of EEXI and CII.

Find out more about this eLearning course.
Find out how we can help with your CII rating

Hit enter or the arrow to search Hit enter to search

Search icon

Are you looking for?