Where does SeaMap get the data from?

SeaMap uses nautical data from the OpenSeaMap project. This nautical data is displayed on top of Google Maps.

What is OpenSeaMap?

OpenSeaMap is an open source, worldwide project to create a free nautical chart. In 2009, OpenSeaMap came into life. This free map includes beacons, buoys and other navigation aids. OpenSeaMap is a subproject of OpenStreetMap and uses its database. See this FAQ for more information about OpenSeaMap.

Can I help improve the nautical data?

Yes. At your desktop/laptop, you can edit seamarks by using the JOSM Editor with a plugin called SeaMapEditor.

Is the nautical data cached on my device?

Yes. It can be cleared at Settings > Clear cache.


49 Responses to “Help”

  1. Joel Halpern Says:

    I downloaded the app and I was under the impression buoys would show. They don’t. And clue.

    • alexvanderlinden Says:

      The bouys are not shown everywhere in the world. SeaMap mainly covers parts in Europe, like the Baltic Sea and the North Sea. Australia is covered as well, but the United States coverage is very poor.

  2. Harrie Heemstra Says:

    Openseamap on pc seems to have newer charts.
    How often do you upgrade the maps?

    can I help?

  3. Joel Halpern Says:


  4. Joel Halpern Says:

    It does. Atleast I know I am not doing anything wrong. Have you found a better app

  5. Harrie Heemstra Says:

    When can we expect a new version?
    I hope the next version can save maps on my sd-card on my smartphone, or did I mis an option?


  6. Joel Halpern Says:

    I am using seamap for my local waters. This is the Manasquan River in Manasquan NJ. I was under the impression that I would see markers and bouys but nothing shows. Any idea? If they are not on a chart any plans to add it.

  7. Ron Netherlands Says:

    Alex it looks great. only what I’m missing are the depth lines eg. 5 and 10 meters. Are you working on that as well

    • alexvanderlinden Says:

      Hi Ron. Showing depths is the much requested feature. However I currently don’t know how to add this information. I mainly rely on information that is available via the openseamap project.

  8. Luis Says:

    Why can’t i get beacons, bouys, and other nav aids when i open the SeaMap app.

  9. Cartalla Allan Says:

    Its not working

  10. Harrie Heemstra Says:


    Again it seems to me that the updates i made on openseamaps are not yet visible on my android smartphone, despite i cleared the cache and restarted the app. On a PC i can see the updates.
    Is ther a delay between

  11. carlos martins Says:

    Dowload version atualized

  12. martin nl Says:

    Great app, but can I import a track?

    • alexvanderlinden Says:

      No. Unfortunately you can’t.

      • ed Says:

        I have been trying this but my area in Lowestoft has minimal marks. I can’t seem to edit using my equipment but my old faithful garmin has all the local nav and bouyage marked. Will anyone take my data and add it to the map? I’m willing and able to chart all the buoyage and sandbanks on my next sailing including depth readings if someone will make use of them. Message me cleanimageuk at

  13. Jean-pierre Elias Says:

    Seamap? Funky make. It only shows an usual google LAND map. The term SEA is odd

  14. grif Says:

    Can I get the distance between any two way points ? If not do you know of an app that provides distance, problem with most the don’t show aids to navigation. ..buoys etc.

  15. Niels Henrik Nielsen Says:

    Wonderfull app. When will we se the deeps on the map?
    How do the users donate money to SeaMap.
    Best regards

    • alexvanderlinden Says:

      Hi Niels.
      Currently I don’t have active plans to show the deeps on the map. Maybe in the future. It depends on available sources.
      And about donating money… well, I would say; buy a beer for you and your friends and enjoy live 🙂

  16. Bader Badraan Says:

    How make mark between 2 points ? Thank you

  17. laya jomar Says:

    i cannot see a Philippines map

  18. Denis Says:

    Dear Sir or Madam

    Thank you in Advance for your support and reply.

    Please let ne know how to set on the map indication of water depth?

    Thank you very much.

    Yours faithfully

    Denis Rykov

  19. Kwan Says:


  20. Gary Says:

    Just installed Sea Map but I can see only a regular map. How do I switch to a chart?

  21. Eminoni Radovu Says:

    Can you display the GPS route from Ba delta to Lautoka Wharf route

  22. Gerson Alexandre de Souza Says:

    Como que eu faço para comprar a carta

  23. Eddy Says:


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: