Just-In-Time Arrival

Background and history

The historical port-arrival pattern

The traditional commercial shipping practice through the 20th century was for ships to maximise voyage speed to arrive at the destination port as early as possible. The rationale:

• Charter party “as fast as ship can reasonably proceed” clauses incentivised speed.
• Berth assignment by arrival sequence: first-come-first-served berth allocation rewarded early arrival.
• Predictable demurrage: ship operators preferred a known wait at anchor over an unpredictable late arrival.
• Bunker prices were low (USD 50-200/tonne through most of the 20th century) so the fuel cost of high-speed transit was modest.

The result: most ships arrived at port hours or days before berth was available, and waited at anchor while burning fuel for hotel load (auxiliary engines for crew accommodation, refrigeration, ventilation, lighting). The 2018 IMO GloMEEP study estimated that approximately 8 to 12% of global shipping fuel consumption was wasted on speed-up-then-wait patterns.

The waste shows up two ways in the operating record. Industry estimates put roughly 15% of marine fuel consumption inside port stays, anchorage and low-speed maneuvering, much of it burned going nowhere, and put the share of total operating time vessels spend at anchor or drifting at 5 to 10%. Those hours are the raw material JIT converts into slow-steaming distance: the question is never whether the wait exists but whether the port will tell the ship about it early enough to absorb it into the approach speed instead of the anchorage. The economics also turned against waiting once bunker prices left the 20th-century range; at the 0.50% sulfur fuel that became mandatory under IMO 2020 the wasted fuel costs real money per day at anchor.

2017 to 2019: GloMEEP study and IMO endorsement

The IMO Global Maritime Energy Efficiency Partnerships Project (GloMEEP), funded by the Global Environment Facility (GEF) and implemented through the IMO with partner countries, conducted a JIT feasibility study in 2017 to 2018 across the major container, tanker and bulk trade routes. The study findings:

• Average anchor-wait time at major container ports: 12 to 24 hours per call.
• Average anchor-wait time at major bulk ports: 24 to 72 hours.
• Theoretical JIT fuel savings if widely adopted: 5 to 8% of global shipping CO2.

The findings prompted MEPC 74 in May 2019 to adopt Resolution MEPC.323(74) Invitation to Member States to encourage voluntary cooperation between the port and shipping sectors to contribute to reducing GHG emissions from ships. The resolution:

• Encouraged port authorities to share berth-availability information with arriving ships.
• Encouraged shipping lines to use the information to slow ships and optimise arrival.
• Did not mandate any specific behaviour but provided industry-level endorsement.

The MEPC.323(74) calculator implements the regulatory framework.

2020 onwards: BIMCO clause and platform proliferation

In October 2020 BIMCO published the JIT Arrival Clause for Time Charters, providing the contractual framework for owner-charterer cooperation on JIT. The clause:

• Permits the charterer to instruct the ship to slow for JIT purposes.
• Allocates the fuel savings (typically to the charterer who pays for the fuel).
• Provides for fuel-saving sharing if both parties contribute to the JIT decision.
• Includes standard procedures for ETA updates and arrival coordination.

The clause has been widely adopted in time charters since 2021 and is now standard in many major dry bulk and tanker charter party templates.

The 2020 to 2024 period also saw the proliferation of port-digitalisation platforms providing the data infrastructure for JIT:

• PortXchange (founded 2018 in Rotterdam): multi-port platform connecting Maersk, Hapag-Lloyd, Ocean Network Express and others to Rotterdam, Antwerp, Hamburg.
• Pronto (Port of Rotterdam in-house): Rotterdam-specific real-time port information.
• Maritime Singapore Connect (Singapore MPA, 2021): Singapore-anchored coordination platform.
• Port of Long Beach Smart Port (US): Long Beach-specific platform.
• Hapag-Lloyd JIT (2022): line-specific platform integrating with multiple ports.

By end-2024 approximately 80% of global container TEU and 50% of bulk DWT was being handled through some JIT-coordination mechanism.

Methodology

Cubic-law fuel saving

The whole case for JIT rests on one piece of physics. For a displacement hull at service speed, calm-water resistance scales with the square of speed, and propulsion power is resistance times speed, so power scales with the cube. The relation is $P \propto v^3$, where $P$ is delivered propulsion power and $v$ is speed through the water. Drop the speed a little and the power demand falls a lot. This is the same admiralty-coefficient regime that drives slow steaming; JIT is slow steaming with a purpose, timed to the berth rather than applied blindly.

Run the numbers on a 10% cut. Power falls to $0.9^3 = 0.729$ of the original, so the per-hour fuel burn drops 27.1%. The voyage takes longer in the same proportion, $1/0.9 = 1.111$, an 11.1% extension. Total voyage fuel is burn-rate times time, so $0.729 \times 1.111 = 0.81$, a 19% saving on the leg that’s slowed. That asymmetry, a 27% instantaneous saving against an 11% time penalty, is why a small slowdown over a long approach pays.

For a 12,000 km container leg that normally runs 20 days at 22 knots, easing to 19.8 knots saves roughly 19% of that leg’s fuel and adds about 2.2 days. The catch is that the 2.2 days only help if the ship would otherwise have spent them swinging at anchor. The engine cube-law fuel calculator implements the relation; in practice the exponent sits between 2.7 and 3.3 once propeller and engine efficiency shifts are folded in, so the 19% figure is an idealization rather than a guarantee.

What the GIA study measured

The strongest evidence for JIT savings comes from a 2022 study commissioned by the IMO-Norway GreenVoyage2050 Project’s Low Carbon Global Industry Alliance (GIA) and carried out by MarineTraffic and Energy and Environmental Research Associates. The study reconstructed real container-ship voyages from AIS tracks and recomputed fuel use under three JIT speed-optimization windows. Optimizing speed across the entire voyage gave a mean per-voyage fuel saving of 14.16%. Optimizing only the last 24 hours gave 5.90%, and the last 12 hours alone gave 4.23%.

The 12-hour result matters more than the headline. It says most of the easy saving sits in the final approach leg, where the wait would otherwise occur, so a port doesn’t need to issue an arrival time days out to capture a real chunk of the benefit. A 4 to 6% cut bought by trimming the last half-day of steaming is the practical floor for container trades; the 14% whole-voyage figure is the ceiling, reachable only when the destination commits to a firm arrival window early.

JIT-specific saving calculation

JIT applies the cubic-law saving only to the part of the voyage that can be slowed without moving the actual berth time. The per-voyage saving is $F_{\text{save}} = \left(1 - \left(\frac{v_{\text{jit}}}{v_{\text{svc}}}\right)^3\right) \cdot \frac{D_{\text{jit}}}{D_{\text{total}}} \cdot F_{\text{voyage}}$, where $v_{\text{svc}}$ is the original service speed, $v_{\text{jit}}$ the reduced JIT speed that still lands the ship at berth-availability, $D_{\text{jit}}$ the distance steamed at the reduced speed, $D_{\text{total}}$ the full voyage distance, and $F_{\text{voyage}}$ the voyage fuel at service speed.

The ratio $D_{\text{jit}}/D_{\text{total}}$ is the lever the GIA study quantified: a whole-voyage slowdown ($D_{\text{jit}} = D_{\text{total}}$) reaches the 14.16% mean, while a last-12-hours slowdown delivers 4.23%. For an Asia-Europe container leg with a 24-hour wait normally absorbed at anchor, easing the speed across the full leg captures most of that 14%. The JIT arrival fuel savings calculator implements this calculation.

Optimum JIT speed

The optimum JIT speed is the slowest speed that still lands the ship at the moment the berth frees, given the constraint of arriving precisely at berth-availability. It’s $v_{\text{jit}} = v_{\text{svc}} \cdot \frac{D_{\text{voyage}}}{D_{\text{voyage}} + v_{\text{svc}} \cdot t_{\text{wait}}}$, where $t_{\text{wait}}$ is the anchor-wait the ship would otherwise have suffered. In words: spread the transit plus the would-be wait across the whole distance and steam at the speed that fills it exactly. Go any slower and the ship arrives late; go any faster and it’s back to waiting at anchor, having burned the difference for nothing. The JIT economic-speed calculator implements this calculation.

Net fuel saving per voyage

The values vary by route, season and prevailing wait patterns; actual savings are typically lower than theoretical due to operational constraints (weather routing, ECA fuel switching, charter party speed warranties).

Requested Time of Arrival and the port-call handshake

Who issues the RTA

JIT lives or dies on a single message: the Requested Time of Arrival, or RTA. The 2020 GIA Just In Time Arrival Guide, published 11 August 2020 by the Low Carbon GIA under the GreenVoyage2050 framework, frames the whole practice around it. The port, not the ship, computes when the berth and the nautical services will actually be free, and sends that time back to the vessel as an RTA. The ship then solves for the speed that hits it. The flow inverts the old habit: instead of the ship declaring an ETA and racing to it, the port declares an RTA and the ship paces to it.

An RTA is only as good as the data behind it. The port has to know berth occupancy, when the current ship will sail, fairway and tide windows, pilot and tug availability, and whether the terminal’s cranes and gangs are ready. Miss any one and the RTA is a guess, and a ship that slows to a wrong guess loses both the saving and its place in the queue. The Guide’s central argument is that the barrier to JIT is rarely the ship; it’s the port’s willingness and ability to publish a firm, early, accurate RTA.

The data points a ship needs

The International Taskforce Port Call Optimisation (ITPCO), a body whose members include major carriers, oil majors, ports and class societies, codified the data set in its Port Information Manual. The manual standardizes the static and dynamic facts a port must publish for arrival planning: chart datum and water-level references, berth and fairway depths, air-draft limits, tidal windows, pilot boarding positions, and the timestamps that define a port call (estimated, requested, planned and actual times for each event). Without a common vocabulary, every port speaks a private dialect and a carrier’s planning system has to translate each one by hand.

The timestamp model is the heart of it. The manual distinguishes the events of a port call, all-fast, commenced cargo, completed cargo, all-clear, each carrying an estimated time, a requested time, a planned time and an actual time. The RTA the ship receives is the requested time of arrival at the pilot boarding place, derived backward from the requested time the berth will be free. Standardizing those four timestamp types across thousands of ports is the unglamorous work that makes JIT scale beyond a handful of digitized terminals.

S-211 and the machine-readable message

A standard vocabulary is worth little if the message itself isn’t machine-readable. That gap is filled by S-211, the Port Call Message Format. The standard grew out of the MONALISA 2.0 and Sea Traffic Management validation projects, is maintained by the International PortCDM Council, and was endorsed by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) and registered in the International Hydrographic Organization’s Geospatial Information Registry. S-211 sits inside the IHO S-100 family alongside the electronic-chart standards, so it shares a governance home with the data ships already carry on the bridge.

S-211 carries the intentions and outcomes of the movements, services and administrative events of a single port call in a structured form any compliant system can parse. A port can emit an RTA as an S-211 message; a carrier’s fleet system ingests it without bespoke integration; the actual times flow back the same way. That two-way, vendor-neutral exchange is what lets a carrier run JIT across many ports rather than only the handful that bought the same commercial platform. S-211 is the standards answer to the platform fragmentation described below.

The charter-party barrier

Utmost despatch rewards racing to anchor

The deepest obstacle to JIT isn’t technical, it’s contractual, and it predates digital ports by a century. Under both voyage and time charters, the owner is bound to prosecute the voyage with “utmost despatch” (or the near-equivalent “all convenient speed”), proceeding without unjustified deviation or delay. Read literally, that clause obliges the master to steam hard and arrive early. A ship that slows on its own to save the charterer’s fuel risks a claim that it breached the despatch obligation, even though the slowdown changed nothing about when cargo actually moved.

The incentive structure under a voyage charter makes it worse. The owner gets paid freight for the cargo, not for time, so an early arrival starts the laytime clock and, once laytime expires, earns the owner demurrage at an agreed daily rate. Demurrage rewards the owner for the ship sitting at anchor: the meter runs whether the ship is alongside or waiting. So the party who pays for the fuel under a voyage charter (the owner) is paid to arrive early and wait, the precise behaviour JIT exists to stop. The GIA Guide names this misalignment as the single largest barrier to adoption.

The BIMCO clauses

BIMCO wrote two clauses to break the deadlock. The Just In Time Arrival Clause for Time Charters (October 2020) lets the charterer instruct the ship to slow for JIT and confirms the master won’t be in breach of the despatch obligation for complying; under a time charter the charterer already pays for bunkers, so the saving lands with the party that ordered the slowdown. The companion Just In Time Arrival Clause for Voyage Charter Parties (2021) tackles the harder case, where slowing forfeits the owner’s demurrage. It supplies a mechanism to agree a reduced speed against a known delay and to compensate the owner for the time saved, typically at or near the demurrage rate, so the owner is no worse off for not waiting.

The voyage clause is the more consequential of the two precisely because it addresses money, not just permission. It establishes the known-delay trigger, a mutual agreement to adjust arrival, and an agreed basis for splitting the resulting saving. Without that compensation term, a rational owner under a voyage charter will keep racing to anchor; with it, the fuel and the demurrage can both be put on the table and divided.

Virtual arrival, the tanker precedent

The voyage-charter problem was solved in the tanker trades long before BIMCO published. In 2009 OCIMF and INTERTANKO convened owners, charterers, P&I clubs, port authorities and marine lawyers to formalize “virtual arrival,” an operational process where a vessel reduces speed to meet an agreed Required Time of Arrival in the presence of a known delay at the discharge port. The arrangement rests on three elements the BIMCO voyage clause later echoed: a documented delay at the discharge port, a mutual agreement to adapt the ship’s arrival, and a charter-party clause that protects the owner from breaching the utmost-despatch obligation while compensating for the time given up.

Virtual arrival also confronted the verification problem head-on. To split a saving fairly, both parties have to agree how much time and fuel were actually avoided, so the OCIMF/INTERTANKO work specified a methodology for quantifying the time saved and the emissions avoided against a baseline speed. That audit trail, the agreed baseline and the agreed measurement, is what turns a goodwill slowdown into an enforceable commercial term. JIT for dry bulk and container trades inherited the structure; the tanker sector simply got there first because its known discharge-port delays made the arithmetic obvious.

Implementation requirements

Digital data exchange

JIT requires real-time data exchange between:

• The arriving ship: current position, ETA, speed, fuel state.
• The destination port authority: berth availability forecast, pilot availability, tide information.
• The terminal operator: cargo readiness, equipment availability.
• The cargo buyer / shipper: cargo readiness, document availability.
• The pilot station: pilot availability, anchor-wait queue.

The data exchange follows IMO Compendium on Facilitation and Electronic Business standards and increasingly uses the Maritime Single Window approach mandated under the SOLAS Convention Chapter VIII (in force from 2024).

Coordination platforms

The major coordination platforms:

• PortXchange: multi-port platform (Rotterdam, Antwerp, Hamburg, others). Approximately 50% of the European container market.
• Pronto: Port of Rotterdam in-house platform. All Rotterdam-bound vessels.
• Maritime Singapore Connect: Singapore MPA platform. All Singapore-bound vessels.
• Long Beach Smart Port: Port of Long Beach platform.
• Inchcape Shipping Services Optic: Asian-focused multi-port platform.
• Veson Nautical: charter-party-integrated JIT platform popular with bulk and tanker operators.
• Smart Port Hamburg: Hamburg-specific platform.

The platforms use APIs to integrate with shipping line ERP systems, port community systems and terminal operating systems.

Charter party integration

The BIMCO JIT Arrival Clause (October 2020) provides the contractual framework:

• The charterer may instruct the ship to slow for JIT.
• The instruction must be given at least 24 hours before the originally-planned arrival.
• Fuel savings accrue to the charterer (since the charterer pays for fuel under time charter).
• If the ship is unable to comply with the JIT instruction (weather, mechanical issues), the charterer is informed promptly.

For voyage charters, the freight rate typically embeds an assumed transit time; JIT savings during voyage charters benefit the shipowner unless the charter party specifies otherwise.

Performance and economics

Typical real-world savings

The 2024 PortXchange annual report identified the following average JIT savings achieved by participating shipping lines:

Maritime Singapore Connect reported similar savings of 3 to 6% across participating Asia-bound vessels.

Capital and operational cost

JIT has minimal capital cost:

• Software subscription: USD 5,000 to USD 50,000 per ship per year, depending on platform and trade pattern.
• Crew training: minimal (the bridge team uses standard ETA-management procedures).
• No physical equipment: no hull modifications, no engine modifications.

The annual fuel saving (for a typical container ship consuming 30,000 t/yr at USD 600/t) of 4 to 6% = USD 720,000 to USD 1,080,000.

The payback period is therefore essentially immediate (less than 1 month). JIT is the lowest-cost CII improvement available to most ship operators.

CII improvement

A 4 to 6% per-voyage JIT saving translates into approximately the same improvement in annual CII attained, since the saving applies across all voyages. For a bulk carrier with attained CII of 5.5 (D rating, 10% above Required), a 5% JIT improvement brings attained CII to ~5.23 (still D but closer to C boundary).

JIT contributes proportionally to the SEEMP combined operational measures calculator along with other operational measures.

EEDI / EEXI: not credited

In contrast to wind-assist, air lubrication and other technical innovations, JIT arrival is not credited under the EEDI or EEXI frameworks because these regulations measure design-phase efficiency at standardised conditions, not operational practice. JIT improves only the operational metrics (CII, EEOI) and fuel cost / emissions.

Notable implementations

Port of Rotterdam Pronto

The Port of Rotterdam’s Pronto platform, operational since 2018 and significantly expanded 2020 to 2024, provides:

• Real-time vessel position tracking via AIS.
• Berth availability forecasting via terminal operator integration.
• Pilot and tug coordination via the Rotterdam Pilots organisation.
• Tide and water-depth predictions from Rijkswaterstaat (Dutch hydrographic service).

By 2024 approximately 80% of Rotterdam-bound deep-sea vessels participate in Pronto, with measured average JIT savings of 4 to 6% per call.

PortXchange multi-port platform

PortXchange operates across approximately 30 ports including Rotterdam, Antwerp, Hamburg, Le Havre, Felixstowe, Algeciras and selected US East Coast ports. The platform:

• Aggregates data from multiple ports for shipping lines operating across multiple destinations.
• Provides line-specific dashboards integrating with ERP systems.
• Includes voyage-level fuel-saving forecasts and post-voyage realisation analytics.

Maritime Singapore Connect

The Maritime and Port Authority of Singapore (MPA) launched Maritime Singapore Connect in 2021 as Singapore’s official JIT platform. Coverage:

• All deep-sea vessels calling at Singapore (~150,000 vessel calls per year).
• Direct integration with the Singapore VTS (Vessel Traffic Service) and the major container terminals (PSA Singapore, Pasir Panjang, Tuas Mega Port).
• API integration with shipping lines including Maersk, MSC, ONE, Cosco, Hapag-Lloyd.

Average JIT savings achieved by participating vessels: 3 to 5% per voyage.

Iron Ore Capesize JIT operations

The Pilbara to East Asia iron ore trade has implemented JIT operations with significant savings:

• BHP, Rio Tinto, Vale as cargo buyers coordinating with Capesize bulk carrier operators.
• Hedland to North Asia: 24-72 hour anchor wait normally avoided through JIT coordination with discharge ports (Pohang, Caofeidian, Qingdao).
• Reported savings: 8 to 12% per voyage on Capesize bulk carriers with full JIT implementation.

Cruise sector

The cruise sector has achieved JIT particularly well due to the predictability of cruise itineraries:

• Caribbean cruise itineraries: minimal anchor wait; JIT achievable with very precise ETA management.
• Mediterranean cruise: similar.
• Cruise lines (Carnival, Royal Caribbean, MSC Cruises) report 2 to 4% fuel savings from JIT-style ETA management.

Critical assessment

Strengths

• Lowest-cost decarbonisation lever: minimal capex, immediate payback.
• Universal applicability: works on any vessel type and any trade route.
• No hull or engine modifications: zero technical risk.
• Proven savings: 2 to 7% per voyage routinely achieved by participating ships.
• Industry alignment: BIMCO clause + IMO endorsement provides framework.

Limitations

• Wait-time-dependent: routes with minimal anchor wait (well-coordinated container schedules) achieve smaller savings.
• Coordination complexity: requires multiple parties (ship + port + terminal + cargo buyer + shipping line) to share data and coordinate.
• Charter party complexity: voyage charter speed warranties may constrain JIT.
• Demurrage risk: if the ship arrives late at the actual berth time, demurrage charges may apply.
• Weather contingency: unexpected weather delays can disrupt JIT planning.
• Terminal disruption: terminal congestion or strike can render JIT planning useless.

Future direction

The 2024 to 2027 work programme for JIT includes:

• Expansion of digital coordination platforms to all major ports.
• IMO standardisation of data formats (Maritime Single Window).
• Integration with FuelEU Maritime intensity reporting (JIT savings count toward intensity reduction).
• Combination with weather routing for compounded savings.
• Possible regulatory mandate (currently voluntary; some industry bodies have called for IMO mandate by 2030).

Future outlook

By 2030 JIT is expected to:

• Be implemented across >90% of global container shipping (vs ~80% in 2024).
• Be implemented across >70% of global tanker shipping (vs ~50%).
• Be implemented across >60% of global bulk shipping (vs ~40%).
• Generate cumulative annual fuel savings of approximately 5 to 7% of total global shipping fuel consumption (vs ~2 to 3% currently).
• Possibly be subject to IMO regulatory mandate by 2027 to 2030.

The principal driver remains the rising cost of fuel under EU ETS Maritime, FuelEU Maritime and the IMO Net-Zero Framework GFI standard from 2027.

Related Calculators

• CII Attained Calculator
• Just-In-Time Arrival Calculator
• Just-In-Time Arrival, Economic Speed Calculator
• IMO MEPC.323(74) - JIT arrival - industry engagement Calculator
• Cube Law Fuel Ratio Calculator
• SEEMP Combined Operational Measures Calculator
• Engine, Thermal Efficiency Calculator
• Engine, CO₂ per kWh Calculator
• CII, SFOC & Fuel Mix Quick Check Calculator
• Wind Assist, Flettner Rotor Calculator
• Wind Assist, Wing Sail / Kite / Soft Sail Calculator
• Air Lubrication System Calculator
• Battery Hybrid SOC & Peak-Shaving Calculator
• Cold Ironing / OPS Offset Calculator
• Weather Routing Savings Calculator
• Weather Routing, Fuel Savings Calculator
• Trim Optimization, Fuel Savings Calculator
• PBCF, Propeller Boss Cap Fin Savings Calculator
• Mewis Duct, Fuel Savings Estimate Calculator
• Pre-Swirl Stator, Energy Saving Calculator
• Bulbous Bow, Retrofit Savings Calculator
• Retrofit Payback Calculator
• MARPOL Annex VI/22, SEEMP Calculator
• MARPOL Annex VI/26, SEEMP revised Calculator
• CII Required Calculator
• CII Rating (A–E) Calculator
• CII Corrective Trajectory Calculator
• EEDI Attained Calculator
• EEDI Required Calculator
• EEXI Attained Calculator
• EEXI Required Calculator
• EPL Required MCR Reduction Calculator
• GFI Attained - WtW Intensity from Fuel Mix Calculator
• GFI Compliance - IMO Net-Zero Framework Calculator
• EU MRV Emissions Report Calculator
• EU MRV to EU ETS Allowance Crosswalk Calculator
• EU ETS, Annual Allowance Cost Calculator
• FuelEU Maritime, GHG Penalty Cost Calculator
• CARB At-Berth Compliance Calculator
• CH₄ Methane Slip Calculator
• LNG Methane Slip, GWP20 / GWP100 GHG Calculator
• LNG, Otto MS / Otto SS / Diesel WtW Calculator
• MARPOL Annex VI, NOx Tier II Limit Calculator
• MARPOL Annex VI, NOx Tier III Limit Calculator
• NOx Tier Compliance Check Calculator
• Norway NOx Fund Levy Calculator
• ECA Fuel-Cost Premium Calculator
• ESI, Environmental Ship Index Calculator
• Poseidon Principles Alignment Calculator
• RightShip GHG Rating Calculator
• MARPOL Annex VI/5, Survey and certification Calculator
• MARPOL Annex VI/6, IAPP certificate Calculator
• IMO DCS, Annual Fuel Report Calculator
• MARPOL Annex VI/28, CII Calculator

See also

• Wind-Assisted Propulsion - parallel technology often combined with JIT
• Air Lubrication Systems - parallel technology
• What is EEDI - design-phase index (not credited for JIT)
• What is EEXI - existing-ship index (not credited for JIT)
• What is CII - operational index that JIT directly improves
• SEEMP I, II and III - operational plan documenting JIT
• EEXI EPL and ShaPoLi - EEXI compliance levers
• CII Corrective Action Plan - corrective measures combining JIT
• Slow steaming and CII - related operational lever
• MARPOL Annex VI - parent regulation
• IMO GHG Strategy - policy framework
• IMO Net-Zero Framework - GFI standard from 2027
• EU ETS for shipping - EU cap-and-trade
• FuelEU Maritime explained - parallel intensity regime
• FuelEU penalties, pooling and multipliers - FuelEU mechanics
• UK ETS for shipping - UK cap-and-trade
• EU MRV Regulation 2015/757 - reporting framework
• IMO DCS vs EU MRV - reporting comparison
• Poseidon Principles - bank-side framework
• Sea Cargo Charter - cargo-buyer-side framework
• RightShip GHG Rating - per-vessel rating
• Green Shipping Corridors - operational corridors
• EUA Market Mechanics for Shipping - allowance market
• Voluntary Carbon Credits in Shipping - parallel mechanism
• CARB At-Berth Regulation - California regional regime
• China DCS - China’s national reporting regime
• Cold ironing and shore power - in-port emission reduction (JIT and cold ironing complement each other)
• Emission Control Areas - regional sulphur and NOx framework
• NOx Tier I, II and III - engine certification regime
• IMO 2020 sulphur cap - global sulphur cap
• Biofuels in shipping - low-carbon fuel pathway
• LNG as marine fuel - dual-fuel pathway
• Methanol as marine fuel - alternative pathway
• Ammonia as marine fuel - zero-carbon pathway
• Heavy fuel oil - residual fuel
• Marine gas oil - distillate fuel
• Specific fuel oil consumption - engine efficiency metric
• Marine diesel engine - main propulsion benefiting from JIT speed reduction
• LNG fuel system - dual-fuel ship handling
• Exhaust gas cleaning system - scrubber technology
• Selective catalytic reduction - SCR for Tier III NOx
• MARPOL Convention - parent IMO treaty
• SOLAS Convention - principal IMO safety treaty (Chapter VIII Maritime Single Window)
• STCW Convention - training and watchkeeping standards
• COLREGs Convention - parallel IMO instrument
• Bulk carrier - principal beneficiary of JIT
• Oil tanker - significant JIT savings
• Container ship - principal vessel type using JIT platforms
• Ro-ro vessel - moderate JIT savings
• Chemical tanker - JIT applicability
• LNG carrier - JIT applicability
• Voyage charter party - voyage-charter JIT considerations
• Time charter party - BIMCO JIT clause for time charters
• Port state control - parallel federal enforcement framework
• Classification society - vessel approval not affected by JIT
• Flag state and flag of convenience - flag-state role
• JIT arrival fuel savings calculator - basic per-voyage saving
• JIT economic-speed calculator - optimum service speed
• MEPC.323(74) IMO Resolution calculator - regulatory anchor
• Engine cube-law fuel calculator - underlying speed-fuel relationship
• Brake thermal efficiency calculator - engine thermal efficiency
• Engine CO2 emission per kWh calculator - engine CO2 rate
• SFOC-to-CII converter - engine SFOC to ship CII rating
• Wind-assist Flettner rotor calculator - parallel wind-assist
• Wind-assist wing sail / kite calculator - parallel wind-assist
• Air lubrication system calculator - parallel technology
• Battery hybrid SOC calculator - battery state of charge
• Cold ironing OPS offset calculator - per-visit emissions reduction (combined with JIT for full in-port savings)
• Weather routing savings calculator - weather routing fuel savings
• Weather routing fuel savings calculator - alternative weather routing
• Trim optimisation calculator - trim optimisation
• PBCF energy-saving device calculator - propeller boss cap fin
• Mewis duct calculator - Mewis duct savings
• Pre-swirl stator calculator - pre-swirl stator savings
• Bulbous bow retrofit savings calculator - bulbous bow savings
• Lifecycle retrofit payback calculator - investment payback
• SEEMP combined operational measures calculator - non-overlapping savings stack
• SEEMP Part I calculator - Part I structure
• SEEMP Part III calculator - Part III CII operational plan
• CII attained calculator - operational AER calculation
• CII required calculator - regulation-driven Required CII
• CII rating calculator - A-to-E rating mapping
• CII corrective trajectory calculator - corrective plan forecast
• EEDI attained calculator - design-phase index
• EEDI required calculator - Required EEDI
• EEXI attained calculator - EEXI as-built calculation
• EEXI required calculator - Required EEXI
• EPL required MCR reduction calculator - EEXI compliance limited MCR
• GFI attained calculator - WtW intensity from fuel mix
• GFI compliance calculator - Net-Zero Framework compliance position
• EU MRV emissions calculator - per-voyage emissions
• EU MRV to EU ETS allowance crosswalk calculator - bridges MRV data to ETS surrender
• MARPOL EU ETS cost calculator - EU ETS surrender cost
• MARPOL FuelEU penalty calculator - FuelEU non-compliance penalty
• CARB at-berth compliance calculator - California compliance check
• Methane slip calculator - LNG dual-fuel methane slip
• Methane slip CO2-equivalent calculator - GWP100 conversion
• LNG well-to-wake calculator - LNG WtW intensity
• Tier II NOx calculator - rated-speed-dependent Tier II
• Tier III NOx calculator - rated-speed-dependent Tier III
• NOx Tier compliance check calculator - integrated tier compliance check
• Norway NOx Fund calculator - national NOx levy
• ECA fuel-cost premium calculator - trade-route ECA economics
• ESI score calculator - Environmental Ship Index voluntary recognition
• Poseidon Principles alignment calculator - lender-side CAS
• RightShip GHG calculator - per-vessel rating
• Survey calculator - Annex VI survey cycle
• IAPP certificate calculator - IAPP issue and endorsement
• IMO DCS report calculator - annual fuel-consumption report
• Reg 28 CII calculator - CII rating
• ShipCalculators.com calculator catalogue - full listing

Additional calculators:

• ETA at Pilot Station - Basic Calc
• Slow Steaming Fuel Savings Calculator

Additional formula references:

• Voy Eta Pilot Station
• Terminal Singapore Tuas Mega Port

Additional related wiki articles:

• BIMCO CII and Emissions Clauses
• Slow Steaming

References

1. IMO MEPC. Resolution MEPC.323(74) - Invitation to Member States to encourage voluntary cooperation between the port and shipping sectors to contribute to reducing GHG emissions from ships. IMO, 17 May 2019.
2. IMO. GloMEEP JIT Arrival Study. IMO Marine Environment Division, 2018.
3. BIMCO. BIMCO Just-In-Time Arrival Clause for Time Charters. BIMCO, Copenhagen, October 2020.
4. Port of Rotterdam Authority. Pronto Annual Report 2024. Rotterdam, 2024.
5. PortXchange. Annual JIT Implementation Report 2024. PortXchange, Rotterdam, 2024.
6. Maritime and Port Authority of Singapore. Maritime Singapore Connect Annual Report 2024. MPA, Singapore, 2024.
7. C40 Cities. Green Ports Forum: Port Digitalisation Status Report. C40, London, 2024.
8. ITF / OECD. Maritime Decarbonisation: Reduce, Restructure, Replace - JIT Section. International Transport Forum, Paris, 2024.
9. Inchcape Shipping Services. Optic Platform Annual Report. Inchcape, London, 2024.
10. Veson Nautical. Just-In-Time Arrival in Charter Party Operations. Veson, Boston, 2023.
11. DNV. Maritime Forecast to 2050 - JIT Arrival Section. DNV, Oslo, 2025 edition.
12. Lloyd’s Register. Just-In-Time Arrival: Practical Implementation Guide. Lloyd’s Register Marine, London, 2024.
13. UNCTAD. Review of Maritime Transport 2024 - Port Operations Section. United Nations Conference on Trade and Development, Geneva, 2024.

Further reading

• IMO. MEPC.1/Circ.884 on Industry Cooperation for JIT Arrival. IMO, 2020.
• DNV. Maritime Forecast to 2050. DNV, Oslo, 2025 edition.
• Hapag-Lloyd. JIT Arrival Operational Manual. Hapag-Lloyd, Hamburg, 2024.

Related formulas

• Just-In-Time Arrival - Economic Speed
• Just-in-Time Arrival