Free Navigation Tool
Interactive Nautical Charts
Explore OpenSeaMap with navigation markers, buoys, lighthouses, harbours, and depth information. Search locations and view maritime features worldwide.
Free to use
No signup required
Instant results
Also in the ClearShip app: OpenSeaMap
Works offline on board where there is no signal, next to the anchor alarm and your boat's maintenance tasks.
More about the app
Discover More Sailing Tools
Register for ClearShip to manage boat maintenance, tasks, checklists, inventory, and collaborate with your crew - plus access all sailing tools.
Unit Converter
Nautical and metric conversions
Wind Converter
Wind speed and Beaufort scale
Phonetic Alphabet
NATO alphabet and text converter
Weather Charts
European weather and wind maps
Sail Trim
Sailing optimization guide
Wind Triangle
True and apparent wind, visualized
VMG Calculator
Optimal upwind and downwind angles
Laylines
Port and starboard tack laylines to a mark
Mayday Emergency
Distress call generator
Navigation Calculator
Course conversion, leeway, and current triangle
Distance & Course
Nautical miles and course between positions
Coordinate Converter
GPS position in degrees, minutes, seconds
Anchor Calculator
Calculate anchor rode length and scope
Crew List
IMO FAL Form 5 crew list generator
Boat Floor Plan Editor
Draw your boat layout with boat symbols, export as SVG