General rule of thumb for fringe length?

#1

I just finished a fun fur scarf using 14 cast-on stiches and size 17 needles. The finished scarf length is approx. 40". I want to make some fringe on either side. Is there a rule of thumb for long to make the tassels?

Thanks!

#2

Not that I’ve ever heard. Start long - you can always cut it.