Frequently Asked Questions

What is OpenSeaMap?
OpenSeaMap is an open source, worldwide project to create a free nautical chart. There is a great need for freely accessible maps for navigation purposes, so in 2009, OpenSeaMap came into life. The goal of OpenSeaMap is to record interesting and useful nautical information for the sailor which is then incorporated into a free map of the world. This includes beacons, buoys and other navigation aids as well as port information, repair shops and chandlerys. OpenSeaMap is a subproject of OpenStreetMap and uses its database.

How can I help?
see "Participate"

How do I register seamarks?
You can edit seamarks via the fullscreen chart by using the powerful JOSM Editor with a plugin called "SeamapEditor" to edit seamarks in offline mode.

When will the chart cover the whole of the Earth's surface?
A completely finished chart will probably never happen, because new things are always being discovered that can be mapped. However, over the next two months, we hope to render the entire Baltic Sea. Two months after that, we hope to have the whole of the North Sea rendered. The remaining oceans are planned to follow at similar intervals. However, it still wouldn't be complete because we then need to add all the navigation aids. These will be collected by community members and then entered into the OpenStreetMap database. You are cordially invited to join in and help! We need every little contribution.

How to use the offline charts?
Offline charts can be downloaded for several navigation programs running on laptops, PDA, PNA, etc. The current position and course of the ship are shown as an overlay. Depending on the program's ablilities navigational tasks will be made easier - even feeding the autopilot is a possibility.

Where can I find more information?
On the OpenStreetMap Wiki

On the sides of the Wiki pages, there are further links, including links to Wikipedia, which offers thousands of articles on navigation and cartography, specific to different countries.

What license is OpenSeaMap under?
All the data in the OpenStreetMap database, including OpenSeaMap data, is under the ODbL. The chart tiles are under the "Creative Commons Attribution Share-Alike 2.0" license. In short, the license stipulates that any use of OSM data is permissible, even for commercial purposes, however OpenStreetMap must be attributed and the resulting data must be released under the same license.

What is OpenStreetMap?
OpenStreetMap is an open source project with the aim of creating a free map of the world. There are currently more than 300,000 contributors in the project! Some of them also contribute to OpenSeaMap. Just as we collect nautical information, there will be data on roads, railway, signs, rivers and much more in the database. We use much of the same data as OpenStreetMap and store all our data in the database. Because contributors collect the data without using copyrighted sources, we own all the data and hence it can be distributed free. For more information about OpenStreetMap visit the OSM-Wiki.