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Is my boat visible?

Check what other boats, apps and Voydar receive from your AIS transponder. Enter your MMSI, or search by boat name, to see the last position we received, which networks heard it and whether your static data is complete.

Not sure where to start? Find your MMSI on your VHF radio’s DSC setup screen, your transponder’s settings or your ship radio licence.

If your boat doesn’t show up

  • Check that the transponder is powered and has a GPS fix. Most show a status light or an alarm when they don’t.
  • Check the VHF antenna, cable and any splitter. A poor antenna connection is the most common reason a working transponder isn’t heard.
  • Class B transponders send every 30 seconds to 3 minutes, and a shore receiver hears boats about 20 to 40 nautical miles away. Out of range of every receiver, nobody ashore hears you.
  • Check the MMSI programmed into the transponder matches your licence. A unit can only be programmed a limited number of times; your dealer can reset it.

Keep your boat in Voydar Helm

Helm Free gives you 1 boat, 3 crew and 5 journeys: the boat’s records, trip plans and its AIS track, private to you and your crew.

Passage planner

Help boats near you be seen

Beacon is Voydar’s receiver network. A small AIS receiver at your marina or at home puts every boat in range on the map, yours included.

Become a Beacon contributor

Why check your AIS?

AIS is only useful if others receive it. A transponder can look fine on deck while its antenna, its programming or the receivers around you mean nobody ashore hears it.

This check shows the boat the way Voydar sees it: when its last position arrived, through which networks, and which of the details other skippers rely on (name, call sign, type and size) are set.

How this works

  1. Identity: the MMSI is checked for 9 digits and read by its leading digits (ITU-R M.585): a boat’s ship station number starts with 2 to 7, its first three digits being the issuing country.
  2. Position: the newest AIS position for the MMSI from a network whose terms let us show it on our pages, from the last 90 days.
  3. Who heard it: the networks behind its newest 2,000 reports of the last 7 days.
  4. Static data: the name, call sign, ship type, dimensions and destination on record for the MMSI, from its AIS static and voyage reports.

This check uses public AIS broadcasts only. Private feeds and Helm boat records never appear here.