What is swail?

The world as a nautical chart

Using data from OpenStreetMap, we design as precise as possible web charts that help you focus on what matters when sailing. Although these charts are not designed for real boat navigation, they show more details than any other online boat simulation. For higher zoom levels, we use Google Maps satellite charts to improve your sailing experience while close to the shores.


Weather and environment predictions

You swail with real time weather data. Wind is provided by NOAA GFS wind model with a 0.5° resolution. Weather data is refreshed every hour and 10 days of weather forecasts are available. We are currently in the process of adding more wind and oceanographic data sources.

Sail on the Web

Using the physics of real boats, we compute your speed, heading and position every second! Thanks to precise coastline detection algorithms, swail is the first online boat simulation that allows you to swail inshore. All this is available at swail, through a map interface which can be displayed on any device, desktop or mobile or our API.

Time Mode

The time mode allows you to see information at different times.

Tip: You can go very fast on a keyboard by using Left and Right Arrows to change time. You can go slowly, hour by hour, by using the Shift key simultaneously.

Pilot Mode

In pilot mode, you're at command! Order a bearing and the crew will manage everything else. The sails, tacks and gybes, backstays, canting keel, ballasts, stabilizers if any. swail computes sailboat positions using weather forecast data and theory boat speeds as inputs.

Tip: You can go very fast on a keyboard by using Left and Right Arrows to change bearing by +- 10 degrees. You can adjust degree by degree by using the Shift key simultaneously.