Fin to Sail Size Calculator

 EN->DE

The fin limits the sail size.

The FSC calculates the maximum sail size depending on the altitude, the air temperature & humidity of a windsurf spot, For the current location, the app can query those data itself (preview).

DisclaimerWindsurfing can be a dangerous sport. I am not responsible for any damage or injury resulting from the use of this website and/or the Fin to Sail Size Calculator (abbreviated FSC).

By using the FSC you agree to the disclaimer.


FSC Info

FSC download:

Open as app!


The FSC App is based on an Excel spreadsheet


The light blue fields are only preset and can be overwritten (by double-clicking) with your own data. Altitude and outside temperature affect the sail size, your weight affects the wind speed. The top left field is used to select the wind units:
0 = m/s, 1 = Bft, 2 = kts, 3 = km/h, 4 = mph.

(On smartphones, the pre-installed browser seems to be the best choice for using the spreadsheet. Otherwise, the FSC App is still available).