This project is read-only.
SimSail calculates the best routing of a sailing boat based on the boat’s speed polar, the wind conditions (based on grib-file weather forecasting), the tidal currents and several parameters. The routing avoids the coastlines and the barriers defined by the user. It can do the routing on several legs can scan several parameters. SimSail use the isochrones method. English or French language.

Vidéo at


  • World coastlines (resolution up to 100 m) with coastal cities and capitals
  • Mercator projection and Great circle (orthodromic circle) with full scrolling in longitude (infinite map)
  • OpenStreetMap
  • Auto save of the session of work
  • Grib file of wind (edition 1 and 2) with display of wind, gusts, isobars, precipitation and total cloud cover
  • Routes, marks, barriers and TSS in GPX format
  • Grib files of currents (edition 1 and 2)
  • Reading of SHOM tidal streams (must be purchased from the SHOM website)
  • All gribs of wind and current can be modified in intensity and lag
  • GPS connection with routing from the boat (when connected to GPS)
  • Routing by Isochrones or by Course made good
  • Routing with multi gribs of wind and current
  • Routing on multiple segments of route
  • Recording of the routings
  • Multiple routings by scan of variables (polar, wind, time and several boats)
  • Analysis of the corrected times between different boats
  • Automatic routing or control of all parameters
  • Routing time step from 1 min to 6 hours
  • Integration of the current into all routing calculations (wind and boat)
  • Coast and barrier avoidance
  • Several polars provided with possibility to modify them
  • Loss of speed during tack
  • Selector of configurations of boat
  • Routing sailing, dual with sailing and motoring with fuel consumption and, motoring
  • Min & max wind force
  • Sea state setting
  • Statistics of the routing
  • Display of all conditions step by step
  • Record and analysis of trace

SimSail is only available for Windows 7, 8 and 10 (32 & 64 bits).

Some polars come from Sailgrib ( but extrapolated data for strong winds have been removed.

The website doesn't allow easy feedbacks from the users but be sure that your feedback is welcome and will be exploited for improvements. Please email to edouard dot halbert at gmail dot com

Last edited Jun 18, 2016 at 8:51 AM by DocHal, version 22