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Sea distance calculator

Sea distance between ports, port to port, in nautical miles, with the days at sea at your own service speed. 1,610 ports.

Service speed
13kn
Route around

Voyage assumptions Draft, departure and sea margin

Draft closes canals below the vessel's sailing draft. Sea margin adjusts the planning days and indicative arrival, not the plotted distance.

How the distance is worked out

Each sea distance between ports is a shortest path across MARNET, the maritime network the European Commission's statistical office publishes and maintains. It is a graph of the lanes merchant traffic actually uses, with the canals and the major straits named as nodes, so the path is constrained to navigable water and every route is plotted on the chart above.

The port to port distance comes out in nautical miles, or sea miles, the unit every distance table and charter party is written in. Sea days are that distance over the service speed you pick. They are steaming days between the two ports and nothing else. Port time, waiting for a berth, bunkering and canal queues all sit on top. Sea margin and an indicative arrival can be added under Voyage assumptions.

How accurate this is, measured

We benchmark the 20 km router against 25 port pairs in the U.S. National Geospatial- Intelligence Agency's Distances Between Ports. The mean difference was 1.9% on long-haul pairs and 4.9% on coastal pairs. The widest differences were 6.8% and 15.5% respectively, because the exact pilot station matters much more over a short distance.

A second check needs no reference table. No voyage can be shorter than the great circle. Across ten open-water legs our routes ran a mean 4.4% longer than that lower bound, with a worst case of 10.5%. That is a check on the network's resolution, not a claim that a vessel would deliberately make the extra detour.

Good enough to compare two discharge options, size a freight budget or sanity-check a laycan. Not a navigational distance, and no master should route a ship on it. The same benchmark is rerun whenever the routing network or its rules change.

What closing Suez costs

Routing Asia to Europe around the Cape of Good Hope instead of through Suez is the single largest swing a distance calculation can take. Both figures are computed by the same routing as the calculator above, with Panama closed as well, so the comparison is Suez against the Cape rather than Suez against a canal most bulk carriers are too deep for.

Rotterdam to Singapore

Via Suez 8,429 nm

Via the Cape 11,881 nm

+3,452 nm about 11.1 extra days at 13 knots

Hamburg to Shanghai

Via Suez 10,902 nm

Via the Cape 14,201 nm

+3,299 nm about 10.6 extra days at 13 knots

Extra distance is only half of it. The additional days are days the vessel is earning nothing else, which is what pushes the freight rate rather than the mileage on its own.

Reference distances

Sea distances between ports on the trades we work, at 13 knots, worked out by the same routing as the calculator. A shipping distance reference, not a schedule.

Selected Baltic Exchange benchmark routes

Two dry-bulk and two tanker routes, and the shorthand a desk uses for them. Route definitions are the Baltic's. The distances are ours and are not Baltic figures. These market references do not describe the cargoes currently open for enquiry.

Route Lane Cargo Distance
C3 Tubarão to Qingdao Iron ore, 160/170,000 mt 11,176 nm
C5 West Australia to Qingdao Iron ore, 160/170,000 mt 3,471 nm
TD3C Ras Tanura to Ningbo Crude, 270,000 mt 5,842 nm
TD20 Bonny to Rotterdam Crude, 130,000 mt 4,533 nm

Sea distance API

Put these distances in your own system

The same routing, reachable from your voyage estimator or freight model. Distances, sea days, canal avoidance and the route geometry.

Request API access

West Africa to Europe

Load Discharge Distance Sea days Via
Lagos NGLOS Rotterdam NLRTM 4,318 nm 13.8 Dover Strait
Abidjan CIABJ Antwerpen BEANR 3,832 nm 12.3 Dover Strait
Luanda AOLAD Algeciras ESALG 3,986 nm 12.8 Strait of Gibraltar

Middle East to Far East Asia

Load Discharge Distance Sea days Via
Jebel Ali AEJEA Shanghai CNSHA 5,748 nm 18.4 Strait of Hormuz, Malacca Strait
Al Fujayrah AEFJR Singapore SGSIN 3,344 nm 10.7 Malacca Strait
Jubail SAJUB Busan KRPUS 6,353 nm 20.4 Strait of Hormuz, Malacca Strait

Europe to Asia

Load Discharge Distance Sea days Via
Rotterdam NLRTM Singapore SGSIN 8,429 nm 27 Suez Canal, Bab-el-Mandeb
Hamburg DEHAM Shanghai CNSHA 10,902 nm 34.9 Suez Canal, Bab-el-Mandeb
Antwerpen BEANR Yokohama JPYOK 11,369 nm 36.4 Suez Canal, Bab-el-Mandeb

Cross Mediterranean

Load Discharge Distance Sea days Via
Piraeus GRPIR El Iskandariya (Alexandria) EGALY 533 nm 1.7 Open water
Barcelona ESBCN Istanbul TRIST 1,442 nm 4.6 Corinth Canal
Genova ITGOA Beirut LBBEY 1,526 nm 4.9 Open water

Common questions

How accurate is a calculated sea distance?

We tested 25 port pairs against the U.S. National Geospatial-Intelligence Agency's Distances Between Ports. The mean difference was 1.9% on long-haul pairs and 4.9% on coastal pairs. The widest differences were 6.8% and 15.5% respectively, because the exact pilot station matters much more over a short distance. A separate open-water check found a mean 4.4% detour over the great circle and a worst case of 10.5%. Good for comparison and budgeting, not for navigation.

How do I measure the nautical distance between two ports?

Pick the load port and the discharge port above and the sea distance between those ports is calculated over the shipping-lane network, in nautical miles and kilometres, with the route drawn on the chart. Searching by name, by country or by UN/LOCODE all work. Measuring it yourself on a chart means stepping the dividers along your intended track against the latitude scale in the margin, never the longitude scale, because only a minute of latitude is a nautical mile.

What speed should I use for the sea days?

Thirteen knots is a reasonable working assumption for a laden bulk carrier and is the default here. Adjust it to the vessel you expect to fix. The days shown are steaming days port to port. They exclude time at berth, waiting for a berth, bunkering and canal transit. Add the margin your trade allows for weather and currents under Voyage assumptions when you need planning days and an indicative arrival date.

Does the calculator account for draft restrictions?

Yes. Open Voyage assumptions and enter the vessel's sailing draft. The route then excludes any canal below it, using 20.1 m at Suez, 15.2 m at Panama, 7.0 m at Kiel and 7.3 m at Corinth. The result states which limits were applied. You can still close Suez or Panama manually under Route around.

Does the calculator account for the Suez Canal being avoided?

Yes. Tick the Suez option and the route is recomputed without it, and Bab-el-Mandeb closes with it, because routing around one and not the other returns a path that enters the Red Sea and stops. Read the passages in the result rather than assuming the Cape: on some Europe to Asia pairs the shortest remaining path runs through Panama, which is only open to you if the vessel is inside the canal's 15.2 metre draft. Close Panama too and you get the Cape routing.

What is the difference between nautical miles and sea miles?

They are the same thing in everyday use. A nautical mile is 1,852 metres, or about 1.15 statute miles, and it is the unit every distance table, charter party and freight calculation in shipping is written in. This calculator shows both nautical miles and kilometres.

Can I use these distances in a freight calculation?

They are a sound basis for an indicative freight estimate, and distance is one of the two inputs that decide a voyage rate, the other being the vessel's daily running cost and bunker consumption. For tanker cargoes the market prices most voyages against Worldscale rather than a straight dollar per tonne, which is a different calculation.

Worldwide cargo desk

Bring us the lane and the cargo

Distance is the easy part. Send the cargo, quantity, load and discharge and the laycan, and we will come back with the tonnage that fits it.