OpenCPN is a simple, concise Chart Plotter Navigator.  It is designed to be used continuously at the helm station of an underway ship or boat, allowing the operator to easily track their position on accurate chart images. Additionally, OpenCPN can display tide and current predictions, as well as information on other suitably equipped vessels in the area.

As a full time cruiser, it became clear that most of the added features on other programs were useless for practical cruising. These eye candy features were resource hogs. I couldn't find a fast running no-nonsense program, so I developed one.

No. OpenCPN is a complete and fully functioning program. This and future upgrades will always be free to download without any gotchas.

A)  It is Open Source software, meaning among other things, that it is
FREE TO DOWNLOAD and use. Escape the commercial paid upgrade treadmill!

B)  It is "concise," meaning that the feature set is optimized for daily use, and excess features (aka "bloatware") are not present. The application is thus smaller and faster, and will run acceptably on as little as a 300 mHz Pentium II Windows 98 computer. Especially, it starts up and shuts down quickly.

OpenCPN is currently at production release stage. There are thousands of active users.  However, minor bugs may be expected. These do not affect normal operation of OpenCPN.

On a personal note, OpenCPN has for years, been the full-time everyday navigator aboard M/V Dyad, our trawler catamaran, cruising from Newfoundland to the Bahamas.

Some familiarity with competitive products is assumed.  Usage is fairly intuitive.  OpenCPN.org provides detailed information about the program and it's use. There are also two very active forums to visit. [Forum links on right-hand column.]

Like all similar programs, OpenCPN's accuracy is dependent upon the accuracy of the positioning input device (e.g. GPS) and the underlying chart database.  As for all such programs, OpenCPN does not remove the responsibility of the operator to LOOK OUT THE WINDOW.

With that said,
OpenCPN will plot the boat position to within about 100 ft of it's true position most of the time, which is the same accuracy as other chart navigation systems. OpenCPN will warn the user if the chart data accuracy does not allow for safe navigation

OpenCPN is optimized as an underway tool, so GPS data is necessary to allow boat position plotting. However, OpenCPN can be used without GPS for planning purposes, such as route and waypoint entry and time/distance calculations.

OpenCPN comes with a few sample charts. These are included to provide instant opportunity to experience the potential of the program. Find all the charts you need for your region at:

Office of Coast Survey  Free nav chart downloads from NOAA.

More chart sources available at dacust.com.

These are the same charts the costly commercial programs use.

If you'd like to develop enhancements to OpenCPN, check out the project on SourceForge.

Current items of interest are:

a)  Testing. Use it, cruise it, abuse it. Your feedback is appreciated.

b)  Documentation. Translation. Writers invited.

c)  Icons, color palettes, etc. Graphic designers invited.