Live Ship Tracking with AIS
FlyRadar doesn't just track aircraft — turn on the marine layer and the same map fills with ships, ferries, tankers and tugs moving through the world's harbors and shipping lanes. The technology behind it is AIS: essentially the maritime cousin of ADS-B.
What is AIS?
The Automatic Identification System is a collision-avoidance system required on most large vessels. Ships broadcast their identity, position, course, speed and voyage details over VHF radio (channels 87B and 88B, at 161.975 and 162.025 MHz). Other ships receive it to avoid collisions; shore stations receive it for traffic management — and trackers receive it to show you the map.
What a vessel broadcasts
- MMSI — a 9-digit Maritime Mobile Service Identity, the ship's radio callsign
- Static data — name, ship type, dimensions, destination, ETA
- Dynamic data — GPS position, course over ground, speed over ground, heading, rate of turn
- Navigational status — underway, at anchor, moored, not under command, restricted maneuverability
Update rate depends on speed: a ship moving fast and turning transmits every few seconds; one at anchor may report only every few minutes.
Class A vs Class B
There are two equipment classes. Class A is mandatory on ships over 300 gross tonnage on international voyages, all passenger ships, and most commercial traffic — it broadcasts with more power, more data fields, and higher priority. Class B is the cheaper, lower-power variant used by smaller vessels, fishing boats and recreational craft. Trackers show both, though Class B coverage is spottier because its 2-watt signal doesn't travel as far.
Terrestrial vs satellite coverage
Like ADS-B, AIS is line-of-sight VHF — coastal receiver stations typically see 20–40 nautical miles out. Beyond that, satellites pick up the signals (S-AIS), which is how mid-ocean positions are tracked. FlyRadar's marine layer comes from open AIS networks, so coverage is densest near coasts and major ports — exactly where vessel traffic is most interesting anyway.
What to look for on the map
- Port approaches — anchorages outside Rotterdam, Singapore or Los Angeles show dozens of ships holding station in neat patterns
- Canals and straits — the Suez Canal, Panama Canal, Bosphorus and Strait of Malacca compress world trade into single-file lines you can watch in real time
- Ferries — short, fast, frequent routes are easy to spot as they shuttle back and forth
Try it: open the map, enable the marine layer, and zoom into the English Channel — you'll see aircraft crossing overhead and ships passing below at the same time.