Emissions and reporting
Design-phase indices under MARPOL Annex VI Chapter 4, the annual CII rating, IMO DCS, and the EU and UK regimes.
Maritime reference · 3,071 calculators
Regulation-referenced calculators for people who run ships.
ShipCalculators.com is a free reference of maritime calculators, each traced to the IMO resolution, EU regulation, or class rule it implements. Every calculator shows the formula it applies and cites the exact MEPC resolution, EU article, or class circular.
- 3,071
- live calculators
- 1,391
- Code lookup cards
- 6
- domains
Browse by domain
The six domains on the drawing above. Each card lists the calculators most often opened in that area.
All 3,071 calculators →Stability and structure
IS Code 2008 criteria, load lines, and hull-girder strength against IACS UR S11.
Cargo and Codes
IMSBC schedules by group, IMDG segregation and packing groups, IBC Chapter 17 ship types.
Navigation and passage
Pre-arrival numbers under SOLAS V/34: squat, under-keel clearance, tide heights, ETA, and roll period.
Machinery and fuels
SFOC, fuel volume correction by ASTM D1250, viscosity at temperature, purifier throughput, and CO2 by Cf.
Commercial and claims
Voyage estimates, TCE, laytime and demurrage under the BIMCO 2013 definitions, and the package limit.
Featured calculator
Attained Carbon Intensity Indicator under MARPOL Annex VI Reg.28, calculation method per MEPC.352(78).
Annual CO2 from BDNs and Cf
17,438t
Deadweight (capacity)
82,000t
Distance sailed, DCS
60,000nm
3.544g CO2 per dwt nm attained
C2026 rating
Worked example. Required CII uses Z = 11% for 2026 under MEPC.338(76); rating boundaries per MEPC.354(78).
What changes next
Dated instruments, each linked to the calculator that produces the number due.
30 Sep2026
EU ETS surrender
100% of 2026 emissions, up from 70% for 2025, under Directive (EU) 2023/959.
EUA liability →31 Mar2027
IMO DCS and EU MRV reports
Fuel consumption data for 2026 under MARPOL Annex VI Reg.27 and the MRV Regulation.
IMO DCS annual →31 May2027
DCS Statement of Compliance
Attained CII and the 2026 rating letter against the MEPC.354(78) boundaries.
CII rating →1 Jan2030
FuelEU intensity step
GHG intensity 6% below 91.16 gCO2e/MJ under Regulation (EU) 2023/1805.
FuelEU GHG intensity →Recently updated
Calculator pages by their last content change.
| Page | Changed |
|---|---|
| Gross Tonnage Calculator: GT and NT by ITC 69 Calculate gross tonnage, GT = K1 × V with K1 = 0.2 + 0.02 log10 V, and net tonnage from … | |
| Wire Rope SWL Calculator: Safe Working Load from MBL Wire rope SWL formula: SWL = MBL ÷ factor of safety. Work out a sling's safe working load … | |
| Sling Angle Calculator: Load in Each Sling Leg Sling angle formula: leg tension = load ÷ (legs × cos α). Find the load in each leg of a … | |
| Draft Survey Calculator: Cargo Weight from Drafts Calculate cargo weight by draft (draught) survey: drafts to the perpendiculars, quarter … | |
| Marine Engine Model Decoder: Read an Engine Designation Decode a marine engine designation such as MAN B&W 6S60ME-C10.7, 12H32/40VP or 9L48/60CR … |
Code lookup library
1,391 reference cards with the edition each follows.
| IMDG dangerous goods by UN number Class, packing group, segregation, placard. | 284 cards, Amdt 42-24 |
| IBC Code Chapter 17 cargoes Ship type, tank type, pollution category. | 236 cards, MEPC.345(78) |
| IMSBC schedules Group, TML, hazards, hold requirements. | 210 cards, Amdt 07-23 |
| SOLAS regulation index Chapter and regulation summaries. | 97 cards |
| Class notations and flag states IACS member notations; Paris and Tokyo MoU lists. | 123 cards |
How every calculator is built and checked
How calculators are checked →Traced to the instrument
Each page names the governing regulation with its resolution number and shows the equation it applies with a symbol legend.
Reproducible by hand
Every calculator carries a worked example a reader can repeat on paper, and where the regulator publishes one, the tool reproduces the regulator's own figure.
Dated, not stamped
A page changes its updated date only when its content changes. The list below is drawn from the build's own history.
Most citedMARPOL Annex VIMEPC.352(78)MEPC.328(76)MEPC.364(79)SOLAS II-2IMSBC CodeIMDG CodeReg. (EU) 2023/1805IS Code 2008
Build directory
Open directory →Every article, calculator and candidate on this site with its publishing status. An internal index: it is not indexed and its links pass no ranking signal.