How to Track a Ship Live — by Name or MMSI
Every large ship at sea constantly broadcasts who it is, where it is, and where it's going. Reading that broadcast takes about a minute once you know the two ways to find a vessel.
Option 1: search by ship name
- Open VesselFlow and tap the search bar.
- Type the vessel's name — two characters is enough to start matching.
- Pick your ship from the results. Names aren't unique at sea, so check the vessel type and flag when several ships share a name.
- The map flies to the vessel and opens its detail sheet.
Option 2: search by MMSI
The MMSI (Maritime Mobile Service Identity) is a 9-digit number that uniquely identifies a vessel's radio — think of it as the ship's phone number. If you have it (from a booking confirmation, a port schedule, or a friend aboard), searching by MMSI is exact: one number, one ship.
Type the 9 digits into the same search bar. No name collisions, no guessing.
Tip: Once you've found a ship the hard way, star it. The watchlist keeps your vessels one tap away and syncs across your devices through iCloud — no account needed.
Reading the detail sheet
- Live gauges (free): speed over ground in knots, course on a compass gauge, heading, and an “updated X ago” freshness stamp so you know exactly how current the fix is.
- Identity (free): vessel type, flag, MMSI and IMO number.
- Voyage (Pro): departure port, destination, route progress, and a live ETA countdown in UTC or your local time.
- Recent track (Pro): the route the ship actually sailed, with a scrubbable speed graph.
- Specs (Pro): length, beam, draught, tonnage, build year, call sign and home port.
No search needed: browse the map
Sometimes you don't have a name — you have a view. The Nearby list shows every vessel currently on screen, sorted by distance from the map center, and the map itself color-codes ships by category (Cargo green, Tankers red, Passenger blue, and so on) with arrows for ships underway. Filters narrow it to a type, to ships underway vs. stopped, or to positions fresher than 30 minutes.
Track your first ship with VesselFlow
Live map, name & MMSI search, and a synced watchlist — free on iPhone & iPad.
FAQ
What is an MMSI number?
A 9-digit identifier for a ship's radio equipment — the vessel's phone number. One MMSI, one ship.
Can I track a ship without knowing its MMSI?
Yes — search by name, then disambiguate with type and flag if several ships match.
How current is a ship's position on the map?
The visible map refreshes about every 60 seconds, and each vessel carries an “updated X ago” stamp. Freshness also depends on AIS coverage where the ship sails.