OpenCPN (Open Chart Plotter Navigator) is a free software maritime chart plotter and navigation software for use underway or as a planning tool.

Developed by a team of active sailors and tested in real world conditions, it has multiple supported chart formats and a variety of data inputs.

[3][4] By using satellite navigation and other NMEA 0183 data feeds, OpenCPN determines a ship's own position and status from sensors such as AIS receivers to automatically plot and track the positions of ships in the neighborhood.

[5] In 2017 Norwegian ENC charts were available for OpenCPN.

[6] This free and open-source software article is a stub.