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CII for container ships: required CII, rating boundaries and calculator

The carbon intensity a container ship must reach each year from 2023 to 2030, by size, with the IMO reference line and the A to E boundaries. Try it on your own ship below.

Updated 2026-10-20

2,375 container ships reported to the EU MRV register for 2025. For a 100,000 dwt container ship the required CII is 6.34 in 2026 and 6.15 in 2027; it is still rated C up to 6.78 in 2026 and 6.58 in 2027.

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Required CII for container ships, 2023 to 2030

Size20232024202520262027202820292030
15,000 dwt17.1116.7516.3916.0315.5515.0814.6114.14
40,000 dwt10.5910.3710.149.929.639.349.048.75
100,000 dwt6.766.626.486.346.155.965.785.59
200,000 dwt4.824.724.624.524.384.254.123.98

g CO₂ per dwt-nautical mile. Required CII = (1 − Z/100) × a × capacity−c, with Z from 5% in 2023 to 21.5% in 2030 (resolution MEPC.338(76) as amended).

The reference line

CIIref=a × Capacity−c

Capacity basis: deadweight (G2, resolution MEPC.353(78)).

Rating boundaries in 2026

SizeA up toB up toC up toD up toE
15,000 dwt13.3015.0617.1519.07above
40,000 dwt8.239.3310.6111.81above
100,000 dwt5.265.966.787.54above
200,000 dwt3.754.244.835.37above

Boundaries are the required CII multiplied by 0.83, 0.94, 1.07, 1.19 (G4, resolution MEPC.354(78)).

Rated D or E?

A ship rated D three years running, or E once, needs a corrective action plan in its SEEMP Part III. How the plan is prepared, or check what EU ETS and FuelEU cost the same ship in the EU ETS and FuelEU calculators.

Questions

What is the required CII for a 100,000 dwt container ship in 2027?

6.15 g CO₂ per dwt-nautical mile: the reference value of 7.12 reduced by 13.625%.

Which capacity is used for the CII of a container ship?

Deadweight.

What are the CII rating boundaries for container ships?

The required CII multiplied by 0.83, 0.94, 1.07 and 1.19. For a 100,000 dwt ship in 2026 a CII up to 5.26 is A, up to 5.96 B, up to 6.78 C, up to 7.54 D, and above that E.

How many container ships report to the EU MRV register?

2,375 in the reporting period 2025, with a median of 15,129 tonnes of CO₂ each.

Check every ship in your fleet

EU ETS, FuelEU, CII and UK ETS for each ship, from the public register or your own data.

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CII for other ship types

Bulk carriersTankersGeneral cargo shipsGas carriersRefrigerated cargo carriersCombination carriersLng carriersRo-ro cargo shipsRo-pax shipsCruise shipsVehicle carriers