A maritime route planner computes the course between two ports over the global network of shipping lanes: the distance in nautical miles, the voyage time at a given speed, and the canal and strait decisions along the way, Suez or the Cape, Panama or Magellan. This guide explains how these planners work, compares the tools available in 2026 from enterprise APIs to browser planners, and shows what the numbers should look like so you can sanity-check any of them.
- Maritime route planners run shortest-path searches over a graph of real shipping lanes, not straight lines.
- The defining features: port-to-port input, canal and strait choices, distance in nautical miles, and ETA at a speed.
- Enterprise tools (Searoutes, SEAMETRIX) serve freight teams at enterprise prices; web planners cover everyone else.
- Good planners reproduce known routes: Rotterdam to Singapore lands near 8,400 nm via Suez.
- For recreational passage planning, a marine route planner with waypoint editing is the better fit.
#How a maritime route planner works
Under every maritime route planner is the same machine: a network graph whose nodes and edges trace the world's shipping lanes, with special edges for canals and straits. Your origin and destination snap onto the network, a shortest-path algorithm runs with your constraints applied, and the result is a realistic course with its length measured along the path. Change one constraint, avoid Suez for example, and the algorithm reroutes around the Cape of Good Hope, adding roughly 3,400 nautical miles to an Asia-Europe run.
#Enterprise: Searoutes and SEAMETRIX
Freight forwarders and operations teams use Searoutes for routing plus CO2 emissions methodology, or SEAMETRIX for chartering-grade distance tables. These are API and platform products priced for companies, typically from several hundred euros per month. If your work involves emissions reporting or vessel scheduling at scale, this is the tier built for it; our sea distance API comparison covers it in detail.
#Web maritime planners
A newer tier runs in the browser: enter two ports, get the route on a map with distance, time at a speed, and canal toggles. The Marine OS route planner is one of them: it suggests the port-to-port course over the open Eurostat shipping-lane network with 16 controllable passages from Suez to Cape Horn, blocks canals too shallow for your entered draft, and then, unlike pure calculators, hands you the route as editable waypoints with weather along the way. For developers, the same engine is available as the Route API.
#Published distance tables
If you need reference numbers rather than a tool, published tables cover the common pairs. Our sea distance pages list 56 port-to-port routes computed on the shipping-lane network, with voyage times at typical speeds, at no cost and with no signup.
Run three known routes: Rotterdam to Singapore should land near 8,400 nm via Suez, Shanghai to Los Angeles near 5,700 nm, and New York to Los Angeles near 4,900 nm via Panama. A planner that misses these by more than a few percent is not worth trusting on the routes you do not know.
Marine OS is marina management software, and the Marine OS app includes a route planner whose engine does maritime port-to-port routing with canal controls, published distance pages, and a developer API. Recreational boaters get waypoint editing, weather, and departure scanning on top of the same engine.
Port-to-port maritime routing in the browser
Two ports in, course out: distance, time at your speed, passages used, and editable waypoints, over the global shipping-lane network.
#Frequently asked questions
Frequently asked questions
Port to port over real lanes, sanity-checked against known routes: that is the whole discipline. For the recreational side, see the best marine route planner apps; for reference numbers, the sea distance pages.
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